JP2005175961A - Imaging apparatus, image sensitivity control method, shutter control method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an imaging apparatus even at a high temperature to provide an image with less image quality deterioration. <P>SOLUTION: The imaging apparatus whose imaging sensitivity is varied limits a range of variable imaging sensitivity when a temperature in the vicinity of an imaging element 15 fixed at a position measured by a temperature sensor 127 is greater than a prescribed temperature. Further, in the case of imaging sensitivity bracket photographing wherein the imaging sensitivity is stepwise changed and photographing is carried out for a plurality of number of times through a single release operation, when the usable imaging sensitivity is limited under an environment at a high temperature and a set bracket width cannot be ensured, the imaging apparatus shifts a bracket reference center value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an imaging device, an imaging sensitivity control method, a shutter control method, and a program, and more particularly, to a still image digital imaging device capable of changing imaging sensitivity, and an imaging sensitivity control method applied to the imaging device. The present invention relates to a shutter control method, and a program for causing a computer to execute the imaging sensitivity control method and the shutter control method.

  2. Description of the Related Art Conventionally, in a digital imaging device using a solid-state imaging device, there is a device that detects the temperature of an imaging device and prohibits shooting by the imaging device when the detected temperature is outside a predetermined range (for example, Patent Documents). 1). Here, when the imaging device is at a high temperature, a lot of noise components are included in the captured image and the image quality deteriorates, so this is avoided.

Conventionally, in an imaging apparatus equipped with both an electronic shutter and a mechanical shutter, an electronic shutter is used when the required exposure time is relatively short, and a mechanical shutter is used when the required exposure time is relatively long. An imaging apparatus has been proposed (see, for example, Patent Document 2).
JP 2000-347284 A JP 2002-176588 A

  However, the above conventional imaging device disclosed in Patent Document 1 has a problem in that shooting is uniformly stopped when the temperature is high, and thus there is a problem that a shooting opportunity is missed. On the other hand, when the imaging device is hot. However, if the imaging sensitivity is lowered, it may be possible to shoot without deterioration in image quality. Therefore, there has been a demand for an imaging device that can shoot without deterioration in image quality even when the imaging device is hot. .

  Note that there is known an ISO bracket shooting mode in which only the imaging sensitivity is converted stepwise while maintaining the same shutter speed and aperture value, and the ISO bracket shooting mode is used. When shooting is performed with high sensitivity, the image quality deteriorates due to noise if the imaging device is at a high temperature.

  Further, in the above-described conventional imaging device that uses the electronic shutter and the mechanical shutter separately shown in Patent Document 2, there is a need for a method that uses the electronic shutter and the mechanical shutter properly without deterioration in image quality at high temperatures.

  The present invention has been made in view of such problems, and an imaging apparatus, an imaging sensitivity control method, a shutter control method, and an imaging apparatus capable of obtaining an image with little image quality degradation even when the imaging apparatus is at a high temperature. And to provide a program.

  In order to achieve the above object, according to the first aspect of the present invention, an imaging unit that images a subject, a temperature measuring unit that measures a temperature in the vicinity of the imaging unit, and an imaging sensitivity of the imaging unit are set. There is provided an imaging apparatus comprising: an imaging sensitivity setting unit configured to perform an imaging sensitivity limiting unit configured to limit a range of imaging sensitivity that can be set by the imaging sensitivity setting unit based on a measurement result of the temperature measurement unit. The

  According to the twelfth aspect of the present invention, the image pickup means for picking up an image of the subject, the temperature measurement means for measuring the temperature in the vicinity of the image pickup means, and the charge accumulated in the solid-state image pickup device included in the image pickup means. The electronic shutter means for controlling the accumulation time, the mechanical shutter means for mechanically controlling the incident time of the subject light flux on the imaging means, and the electronic shutter means based on the measurement result by the temperature measuring means And an image pickup apparatus having a shutter selection operation means for selecting and operating one of the mechanical shutter means.

  According to the invention of claim 14, in the imaging sensitivity control method applied to an imaging apparatus comprising an imaging means for imaging a subject and a temperature measurement means for measuring a temperature in the vicinity of the imaging means, An imaging sensitivity setting step for setting an imaging sensitivity in the imaging unit; and an imaging sensitivity limiting step for limiting a range of the imaging sensitivity set by the imaging sensitivity setting step based on a measurement result by the temperature measuring unit. An imaging sensitivity control method is provided.

  According to a twenty-first aspect of the present invention, there is provided an imaging unit that images a subject, a temperature measuring unit that measures a temperature in the vicinity of the imaging unit, and a charge accumulated in a solid-state imaging device included in the imaging unit. In the shutter control method applied to an image pickup apparatus comprising: an electronic shutter means for controlling the accumulation time; and a mechanical shutter means for mechanically controlling the incidence time of the subject light beam on the image pickup means, the temperature There is provided a shutter control method comprising a shutter selection operation step of selecting and operating one of the electronic shutter means and the mechanical shutter means based on the measurement result by the measurement means.

  Furthermore, a program for causing a computer to execute the imaging sensitivity control method and the shutter control method is provided.

  According to the present invention, in an imaging apparatus capable of varying imaging sensitivity, the range of imaging sensitivity that can be varied is limited when the temperature in the vicinity of the fixed imaging element measured by the temperature measuring unit is higher than a predetermined temperature. This makes it possible to obtain an image with little image quality degradation even when the imaging device is at a high temperature.

  In addition, in imaging sensitivity bracket shooting in which imaging sensitivity is changed in stages with a single release operation, the imaging sensitivity that can be used in high temperature environments is limited, and the bracket width that is set If it cannot be secured, the bracket reference center value is shifted. This makes it possible to obtain a plurality of images having a stepwise exposure width intended by the photographer and having little image noise.

  Note that the same effect can be obtained even if the bracket width set as described above is limited.

  The same effect can be obtained by correcting the imaging sensitivity by digital calculation when the bracket value on the high sensitivity side determined by the bracket width exceeds the upper limit value of the usable imaging sensitivity range. Can be obtained.

  Also, when the bracket value on the high sensitivity side determined by the bracket width exceeds the upper limit value of the usable imaging sensitivity range, the bracket value on the high sensitivity side is changed to the upper limit value. The same effect can be obtained.

  Furthermore, the imaging apparatus includes an electronic shutter unit and a mechanical shutter unit, and selects and operates either the electronic shutter unit or the mechanical shutter unit according to the measurement result of the temperature measuring unit. Specifically, by using the mechanical shutter means at high temperatures, it is possible to discharge smear components accumulated in the transfer path before imaging, and it is possible to prevent taking an image with a lot of imaging noise. .

  In addition, by giving a warning when the imaging sensitivity is changed, it is possible to notify the photographer of the change.

  Further, when the imaging sensitivity is changed, exposure parameters such as an aperture value and the like are again calculated and set at the shutter speed. As a result, an image with an intended exposure can be obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 2 is a side sectional view showing the configuration of the imaging device according to the embodiment of the present invention. This imaging apparatus is a single-lens reflex digital camera.

  In FIG. 2, reference numeral 1 denotes an image pickup apparatus main body, and 2 denotes a photographing lens that forms an object image on an image forming surface. The taking lens 2 is detachable from the image pickup apparatus main body 1 and can be exchanged via a main body mount (not shown). The photographing lens 2 includes an imaging lens 3 for forming an object image on an imaging surface, and a lens driving device 4 for driving the imaging lens 3, and a diaphragm for performing exposure control. A blade group 5 and a diaphragm driving device 6 for driving the diaphragm blade group 5 are provided.

  Although the imaging lens 3 is illustrated in a simplified manner in FIG. 2, the imaging lens 3 is composed of one or a plurality of lenses, and may be a single focal length (fixed focal point) lens, a zoom lens, or a step zoom. A lens having a variable focal length such as a lens may be used.

  In FIG. 2, reference numeral 7 denotes a main mirror, which guides a subject image formed by the taking lens 2 to a focusing screen 8 to be described later, transmits part of the image, and passes through a submirror 12 to be described later to detect a focus detection device to be described later. This is a mirror for guiding to 13. The main mirror 7 is configured to be movable selectively between a position where a subject image can be observed with a finder and a retreat position where the main mirror 7 is retreated from the optical path of the subject light beam at the time of photographing by a mirror driving device (not shown). .

  Reference numeral 8 denotes a focusing screen. The subject light beam guided by the photographing lens 2 is reflected by the main mirror 7 and is imaged on the focusing screen 8. A subject image observed from the viewfinder is a subject image formed on the focusing screen 8. Reference numeral 9 denotes an optical member that converts and reflects an object image formed on the focusing screen 8 into an erect image. In the present embodiment, the optical member 9 includes a penta roof prism. Reference numeral 10 denotes an eyepiece device that causes the subject image converted and reflected to an erect image by the optical member 9 to reach the eyes of the photographer.

  Reference numeral 11 denotes a photometric device, which measures the luminance of a subject image formed on the focusing screen 8 during viewfinder observation via an optical member 9. In the imaging device according to the present embodiment, the photometric device 11 includes Exposure control at the time of exposure is performed based on the output signal.

  Reference numeral 12 denotes a sub-mirror that reflects the subject light partially transmitted through the main mirror 7 and guides the subject light to a focus detection device 13 (described later) disposed on the lower surface of a mirror box (not shown). The sub-mirror 12 is linked to the main mirror 7 or a mirror driving device (not shown) that drives the main mirror 7, and is in a guiding position for guiding subject light to the focus detection device 13 during viewfinder observation, and in the optical path of the subject luminous flux during photographing. It is configured to be movable to a retracted position retracted from.

  A focus detection device 13 controls the lens driving device 4 of the photographing lens 2 based on an output signal of the focus detection device 13, and performs focus adjustment by the imaging lens 3. A mechanical shutter device 14 mechanically controls the incident time of the subject light flux on the image forming surface. The mechanical shutter device 14 shields the subject luminous flux during finder observation and retracts from the optical path of the subject luminous flux in response to a release signal during photographing, and retracts from the optical path of the subject luminous flux during finder observation. In addition, this is a focal plane shutter having a rear blade group 14b that shields the subject luminous flux at a predetermined timing after the traveling (drive) of the front blade group 14a is started at the time of photographing.

  Reference numeral 15 denotes a solid-state image sensor that captures a subject image formed by the photographing lens 2 and converts it into an electrical signal. As this solid-state imaging device 15, a known two-dimensional imaging device is used. There are various types of imaging devices such as a CCD type, a MOS type, and a CID type, and any type of imaging device may be adopted. In this embodiment, a plurality of photoelectric conversion elements (photographs) are used. Sensor) is two-dimensionally arranged, and an image sensor of an interline CCD (charge coupled device) in which signal charges accumulated in each photosensor are output via a vertical transfer path (vertical transfer CCD) and a horizontal transfer path. Is adopted. The solid-state imaging device 15 has a so-called electronic shutter function that controls the accumulation time (shutter time) of charges accumulated in each photosensor. Reference numeral 16 denotes an electric substrate, which is electrically and mechanically coupled to the solid-state imaging device 15 and holds them.

  FIG. 3 is an external top view of the imaging apparatus, and FIG. 4 is an external rear view of the imaging apparatus.

  3 and 4, 112 is an AE (automatic exposure) lock button, and 113 is an AF (autofocus) distance measuring point selection button. Reference numeral 140 denotes an external liquid crystal display device having an external display function for displaying photographing conditions and the like.

  Reference numeral 114 denotes a release button for performing a photographing operation. The release button 114 is configured to turn on the switch SW1 in the first stroke and turn on the switch SW2 in the second stroke.

  Reference numeral 115 denotes a main electronic dial. For example, the switch sense circuit 125 detects the rotation direction and the number of rotation clicks of the main electronic dial 115 by sending a 2-bit signal with a 90 ° phase shift to the switch sense circuit 125 described later. Is done. Depending on the rotation direction and the number of rotation clicks, a numerical value is input to the imaging apparatus or the shooting mode is switched in combination with another operation SW.

  117 is a photographing mode selection SW, 118 is an AF mode selection SW, and 119 is a photometry mode selection SW.

  When the main electronic dial 115 is rotated while pressing the shooting mode selection SW 117, the mode changes as Tv priority (shutter priority) → Av priority (aperture priority) → Manual → Program → Tv priority → Av priority → Manual → Program. And can be set to the mode intended by the photographer. When the main electronic dial 115 is rotated in the reverse direction, the mode is changed as follows: program → manual → Av priority → Tv priority → program →.

  If the Tv priority mode is set by the shooting mode selection SW 117 and the main electronic dial 115, the Tv value (shutter speed, exposure time) desired by the photographer is set by rotating the main electronic dial 115. can do.

  When the Av priority mode is set by the shooting mode selection SW 117 and the main electronic dial 115, the Av value (aperture value) desired by the photographer is set by rotating the main electronic dial 115. Can do.

  Reference numeral 126 denotes a drive mode selection SW for setting the continuous shooting mode. By simultaneously pressing the photometry mode selection SW 119, an AEB setting mode capable of setting AEB is selected.

  Reference numeral 120 denotes an LCD monitor device (liquid crystal display) that displays a photographed image. Since LCD monitor device 120 according to the present embodiment is a transmissive type, an image cannot be visually recognized only by driving LCD monitor device 120, and a backlight illumination device (not shown) is always required on the back surface. . Reference numeral 121 denotes a monitor switch for turning on / off the backlight illumination device of the LCD monitor device 120.

  Reference numeral 116 denotes a sub electronic dial having the same function as the main electronic dial 115. When the manual mode is set by the shooting mode selection SW 117 and the main electronic dial 115, the aperture value is set by the sub electronic dial 116, and the program mode (P), shutter priority mode (Tv), aperture priority mode ( When (Av) is set, the sub-electronic dial 116 is used to set the exposure correction amount for changing the appropriate exposure amount obtained by photometry.

  Reference numeral 122 denotes a dial lock switch that locks the input function of the sub electronic dial 116, and reference numeral 123 denotes a main switch that prohibits all operations of the imaging apparatus.

  Reference numeral 124 denotes a menu button for selecting a mode when displaying an image on the LCD monitor device 120 or at the initial setting of the imaging device. When selecting each mode, the menu button 124 is pressed while pressing the menu button 124. The electronic dial 116 is rotated to select a desired mode. When the desired mode is selected, the selection / setting is completed when the menu button 124 is released.

  FIG. 1 is a block diagram illustrating an internal configuration of the imaging apparatus. In FIG. 1, the same components as those shown in FIGS. 2 to 4 are denoted by the same reference numerals.

  In FIG. 1, the imaging device mainly includes a lens driving device 4 that drives the photographing lens 2, a mechanical shutter device 14, a solid-state imaging device 15, an analog signal processing circuit 20, an A / D converter 22, a main signal processing circuit 24, The memory 26, a D / A converter 28, an external display device 30, a compression / decompression circuit 32, a memory card 34, a control circuit 36, a CPU (central processing circuit) 38, and the like.

  A switch sense circuit 125 detects the operation state of each switch and transmits it to the CPU 38.

  The switch sense circuit 125 is connected to a switch SW (1) 114a that is turned on by the first stroke of the release button 114 and a switch SW (2) 114b that is turned on by the second stroke of the release button 114. When the switch SW (2) 114b is turned on, the release operation is started.

  The switch sense circuit 125 is connected to the main electronic dial 115, the sub electronic dial 116, the shooting mode selection SW 117, the AF mode selection SW 118, and the photometry mode selection SW 119. The switch sense circuit 125 indicates the state of each dial / SW. Is detected and transmitted to the CPU 38.

  The amount of light of the subject light flux that has passed through the photographic lens 2 is regulated by the diaphragm blade group 5 and the mechanical shutter device 14 and projected onto the solid-state image sensor 15. At this time, in the solid-state imaging device 15, the charge accumulation time is controlled via the control circuit 36. The subject image formed on the light receiving surface of the solid-state imaging device 15 is converted into a signal charge of an amount corresponding to the amount of incident light by each photosensor and sequentially read out as an imaging output signal, and then an analog signal processing circuit 20 is supplied.

  The analog signal processing circuit 20 includes a CDS clamp circuit, a gain adjustment circuit, and the like, and appropriately processes an imaging output signal (analog electrical signal) input from the solid-state imaging device 15 based on control of the control circuit 36. The signal output from the analog signal processing circuit 20 is converted into a digital signal by the A / D converter 22 and then sent to the main signal processing circuit 24.

  The main signal processing circuit 24 includes a gain adjustment circuit 40, an offset circuit 42, a histogram generation circuit 46, a digital signal processing circuit 48, and the like. The data signal output from the A / D converter 22 is sent to the histogram generation circuit 46 and the digital signal processing circuit 48 via the gain adjustment circuit 40 and the offset circuit 42.

  The histogram generation circuit 46 creates a histogram indicating the distribution of the integrated value of the image sensor signal with respect to the signal level from the data for one screen sent from the A / D converter 22. Then, a gain value and an offset value are determined based on this histogram calculation, and this is sent to the CPU 38. The CPU 38 controls the gain adjustment circuit 40 and the offset circuit 42 via the control circuit 36 based on the sent gain value and offset value.

  The data signal output from the A / D converter 22 is subjected to gain and offset adjustment by the gain adjustment circuit 40 and the offset circuit 42 and then sent to the digital signal processing circuit 48. The digital signal processing circuit 48 includes a luminance (Y) signal generation circuit and a color difference (C) signal generation circuit, and performs Y / C signal processing on the signal input from the offset circuit 42. The image data that has been subjected to Y / C signal processing by the digital signal processing circuit 48 is temporarily stored in the memory 26.

  The image data stored in the memory 26 is decoded, converted to an analog signal by the D / A converter 28, and supplied to the LCD monitor device 120. In this way, the image captured by the solid-state image sensor 15 is displayed on the LCD monitor device 120. On this LCD monitor device 120, a still image shot based on a shooting start signal generated by pressing the release button 114 or the like is displayed.

  The signal converted into an analog signal by the D / A converter 28 is output from the video output terminal 50 as a video output signal.

  Further, the image data of the main imaging acquired in response to the input of the imaging start signal is guided from the memory 26 to the compression / decompression circuit 32, where it is compressed according to a predetermined image compression format (for example, JPEG). The data is recorded on a memory card 34 as a portable recording medium.

  The portable recording medium may be a smart media or an IC card in addition to a memory card.

  The image data recorded in the memory card 34 can be read out via the CPU 38. The image data read out from the memory card 34 is decompressed and reproduced by the compression / decompression circuit 32, and then the memory 26, D It is output to the LCD monitor device 120 via the / A converter 28 or output to the video output terminal 50 and can be supplied to other external devices.

  The CPU 38 is connected to the photometry device 11, the focus detection device 13, the control circuit 36, the histogram generation circuit 46, the digital signal processing circuit 48, the memory 26 and the memory card 34, the switch sense circuit 125, and the like, and is exposed according to a predetermined algorithm. Various calculations such as the value and the focal position of the photographic lens 2 are performed, and control such as automatic exposure control, auto focus, auto strobe, and auto white balance is comprehensively managed. Further, the CPU 38 sets a corresponding circuit based on various signals input from the operation unit such as the release button 114, the main electronic dial 115, the sub electronic dial 116, the photographing mode selection SW 117, the AF mode selection SW 118, and the photometry mode selection SW 119. Control.

  The output signal of the photometric device 11 is sent to the CPU 38, which calculates the exposure control value. The calculated exposure control value is sent from the CPU 38 to the control circuit 36, and control such as automatic exposure control, auto strobe, and auto white balance is performed via the control circuit 36.

  The temperature sensor 127 is a sensor that measures the temperature near the solid-state imaging device 15.

  The buzzer 128 is a sound generating means mainly used for a warning at the time of shooting.

  The control circuit 36 controls the drive circuit of the solid-state imaging device 15 based on the exposure control value sent from the CPU 38, and controls the charge accumulation time of the solid-state imaging device 15 in the electronic shutter control mode. In the shutter control mode, the opening / closing timing of the mechanical shutter device 14 is controlled, and further, the aperture driving device 6 is controlled during exposure.

  As described above, the exposure control of the imaging apparatus according to the present embodiment has two exposure control modes, and the control circuit 36 and the CPU 38 automatically switch between the electronic shutter control mode and the mechanical shutter control mode. It is configured as follows.

  5 to 7 are diagrams for explaining a shooting sequence of the imaging apparatus in the electronic shutter control mode and the mechanical shutter control mode described above, and FIG. 5 shows a shooting sequence in the mechanical shutter control mode. 6 shows an imaging sequence in the electronic shutter control mode, and FIG. 7 shows a control sequence of the mechanical shutter device 14 in the electronic shutter control mode in FIG.

  First, with reference to FIG. 5, a photographing sequence in the mechanical shutter control mode will be described. 5A shows the leading blade travel start signal, FIG. 5B shows the trailing blade travel start signal, FIG. 5C shows the leading / rear blade driving state, and FIG. 5D shows the operating state of the solid-state imaging device (CCD) 15 respectively. Show.

  In FIG. 5, when the CPU 38 determines to perform exposure control in the mechanical shutter control mode, the control circuit 36 outputs a leading blade travel start signal to the mechanical shutter device 14 based on the exposure control value sent from the CPU 38. The driving of the leading blade group 14a is started, and the solid-state imaging device 15 is operated to start the charge accumulation operation. Based on the Tv value (target exposure time) determined based on the exposure control value sent from the CPU 38, the control circuit 36 outputs a rear blade travel start signal to the mechanical shutter device 14 to drive the rear blade group 14b. The exposure operation to the solid-state imaging device 15 by the leading blade group 14a and the trailing blade group 14b is controlled.

  The solid-state imaging device 15 continues the charge accumulation operation even after the rear blade group 14b of the mechanical shutter device 14 is driven (the hatched portion in FIG. 5C). In addition, the solid-state image sensor 15 removes the influence of smear generated when light is incident more than necessary at the time of exposure, so that the signal charges accumulated in the photoelectric conversion elements constituting the solid-state image sensor 15 are transferred to the vertical transfer CCD. Before moving, smear components leaking into the vertical transfer CCD are read out and swept away. Thereafter, the solid-state imaging device 15 ends the charge accumulation operation, transfers the signal charge accumulated in the photoelectric conversion element to the vertical transfer CCD, and performs normal readout which is a signal charge read operation, and performs an imaging sequence for one frame. End.

  Next, a shooting sequence in the electronic shutter control mode will be described with reference to FIG. 6A shows the leading blade travel start signal, FIG. 6B shows the trailing blade travel start signal, FIG. 6C shows the leading / rear blade driving state, and FIG. 6D shows the operating state of the solid-state imaging device (CCD) 15 respectively. Show.

  In FIG. 6, when the CPU 38 determines to perform exposure control in the electronic shutter control mode, the control circuit 36 first outputs a leading blade travel start signal to the mechanical shutter device 14 based on the exposure control value sent from the CPU 38. Then, the driving of the leading blade group 14a is started. Then, after the front blade group 14a is completely opened, the control circuit 36 operates the solid-state imaging device 15 to start the charge accumulation operation, and is determined based on the exposure control value sent from the CPU 38. The charge accumulation time is controlled by the Tv value.

  The control circuit 36 outputs a trailing blade travel start signal to the mechanical shutter device 14 in accordance with the timing of completion of charge accumulation, starts driving the trailing blade group 14b, and puts the solid-state imaging device 15 in a light-shielding state. To do. The solid-state imaging device 15 transfers the signal charge accumulated in the photoelectric conversion element to the vertical transfer CCD at the end of the charge accumulation time, and performs normal readout, which is a signal charge readout operation, at the timing when the trailing blade group 14b is driven. The photographing sequence for one frame is finished.

  Next, a control sequence of the mechanical shutter device 14 in the electronic shutter control mode will be described with reference to FIG. 7A shows the leading blade travel start signal, FIG. 7B shows the trailing blade travel start signal, FIG. 7C shows the leading / rear blade driving state, and FIG. 7D shows the operating state of the solid-state imaging device (CCD) 15 respectively. Show.

  In FIG. 7, when the exposure operation starts, the leading blade group 14a of the mechanical shutter device 14 starts to be driven by a leading blade travel start signal from the control circuit 36, and actually opens the main body opening portion (hereinafter referred to as “aperture”). The leading blade time lag, which is the time to start, is set to T1, the leading blade curtain speed, which is the time for the leading blade group 14a to travel through the aperture, is set to V1, and the trailing blade group 14b of the mechanical shutter device 14 at the end of the exposure operation is controlled by the control circuit 36. The trailing blade time lag, which is the time until the rear blade group 14b travels through the aperture, is set to T2 with the trailing blade time lag, which is the time from the start of driving by the trailing blade travel start signal from Then, the leading blade time lag T1, leading blade curtain speed V1, trailing blade time lag T2 and trailing blade curtain speed V2 are mechanically The factors have the solid dispersion with the time width within a certain range.

  Originally, the driving of the mechanical shutter device 14 starts driving the leading blade group 14a by the leading blade travel start signal after the photographing sequence of the front frame (normal reading ends), and detects the driving end of the leading blade group 14a. If the signal charge is normally read after the end of driving of the leading blade group 14a is detected by a switch or the like, exposure control can be performed reliably.

  However, if the next operation is started after waiting for the end of each operation, the time required for the shooting sequence per frame becomes long, and the operation status of each switch is monitored before the next operation is started. When the operation is started, the time required for the sequence becomes long, and as a result, high-speed continuous shooting by the imaging apparatus becomes impossible.

  In view of this, the imaging apparatus according to the present embodiment is configured to manage all operation start timings according to time and perform overlap control of each operation in the electronic shutter control mode.

  In FIG. 7, the controller circuit 36 outputs a leading blade travel start signal T1 min before the end of normal reading of the previous frame, and the normal reading of the previous frame and the driving of the leading blade group 14a of the mechanical shutter device 14 of the next frame exceed the T1 min time. Wrap it. The charge accumulation of the next frame is started after (T1max + V1max) from the time when the leading blade travel start signal is output.

  The time between the end of normal reading of the previous frame and the start of charge accumulation of the next frame is (V1max + (T1max−T1min)), which is determined by the latest time of the leading blade curtain speed V1 and the variation time of the leading blade time lag T1. become.

  In addition, the controller circuit 36 outputs a trailing blade travel start signal T2 min before the charge accumulation of the photographing frame is completed, and overlaps the charge accumulation of the photographing frame and the driving of the rear blade group 14b of the mechanical shutter device 14 for a time T2min. The normal reading start of the imaging frame is performed after (T2max + V2max) from the time when the trailing blade traveling start signal is output.

  The time between the charge accumulation end of the photographing frame and the normal reading start is (V2max + (T2max-T2min)), and is determined by the latest time of the trailing blade curtain speed V2 and the variation time of the trailing blade time lag T2. .

  As described above, during exposure control in the electronic shutter control mode used in the image pickup apparatus according to the present embodiment, the driving of the front blade group 14a of the mechanical shutter device 14 of the photographing frame and the normal reading operation of the front frame are overlapped and controlled. The time between the end of normal reading of the frame and the charge accumulation of the photographing frame is shortened, and the charge accumulation operation of the photographing frame and the driving of the rear blade group 14b of the mechanical shutter device 14 are overlapped to complete the end of charge accumulation of the photographing frame and start the normal reading. It is possible to shorten the time until.

  Also, if a higher-performance mechanical shutter device capable of high-speed seconds with a higher curtain speed is used, a mechanical device with less variation in the leading / rear blade time lag can be achieved without using a high-performance mechanical shutter device. In the case of a shutter device, the time between the end of normal reading of the previous frame and the start of charge accumulation of the next frame and the time between the end of charge accumulation of the shooting frame and the start of normal reading can be shortened. The required time can be shortened and high-speed continuous shooting is possible.

  By the way, in the imaging device used in the present embodiment, as described with reference to FIGS. 5 and 6, in the electronic shutter control mode and the mechanical shutter control mode, the mechanical shutter device 14 and the solid-state imaging device 15 are not used. Since the operation sequence is different, the required time per sequence is different. In particular, in the mechanical shutter control mode shown in FIG. 5, since vertical transfer is performed before normal reading, the time required per sequence is longer than in the electronic shutter control mode shown in FIG. It will be disadvantageous.

  Therefore, the imaging apparatus according to the present embodiment is configured such that the CPU 38 switches the control sequence in accordance with the shutter time during exposure control and the temperature in the vicinity of the solid-state imaging device 15 by taking advantage of the respective control sequences. Has been.

  That is, in the electronic shutter control mode, since the required time per sequence is short and the exposure time is determined only by controlling the charge accumulation time of the solid-state imaging device 15, it is possible to control the ultra-high shutter speed. Controls the high-speed shutter speed side. On the other hand, the low shutter speed side control is performed in the mechanical shutter control mode. In the execution of this mechanical shutter control mode, smear components that have leaked into the vertical transfer CCD are read out and swept away in order to eliminate the effect of smear that occurs due to excessive light incident during long-time exposure. To. As a result, it is possible to read a signal having a good S / N (signal-to-noise) and free from smear.

  FIG. 8 is a diagram illustrating a region in which the electronic shutter control mode and the mechanical shutter control mode are executed in the imaging apparatus according to the present embodiment along the shutter time.

  In the figure, the electronic shutter control mode is set to perform shutter speed control at a speed higher than 1/30 seconds, and the mechanical shutter control mode is set to perform shutter speed control at a speed lower than 1/500 seconds, In addition, between 1/500 seconds and 1/30 seconds, one of the electronic shutter control mode and the mechanical shutter control mode is selected according to the temperature in the vicinity of the solid-state imaging device 15.

  That is, noise components in the image data increase when the solid-state image sensor 15 and its surrounding electric circuits become high temperature. Therefore, when the temperature in the vicinity of the solid-state image sensor 15 detected by the temperature sensor 127 is 45 ° C. or higher, the shutter The mechanical shutter control mode is selected with an upper limit of speed 1/500 seconds, the electronic shutter control mode is selected on the side faster than 1/500 seconds, and in addition, the vertical transfer CCD from the photoelectric conversion element of the solid-state image sensor 15 Read out the smear component that leaked into and remove it. On the other hand, when the temperature in the vicinity of the solid-state imaging device 15 is lower than 45 ° C., the shutter speed is reduced to 1/30 seconds and the electronic shutter control mode is selected, and the mechanical shutter control mode is selected on the lower speed side than 1/30 seconds. To do.

  As described above, in the imaging apparatus according to the present embodiment, the CPU 38 selects either the electronic shutter control mode or the mechanical shutter control mode based on the set shutter speed and the detection result of the temperature sensor 127. Do it accordingly.

  Next, a selection procedure in the case where the user preselects a method for setting the imaging sensitivity when the temperature in the vicinity of the solid-state imaging device 15 is equal to or higher than a predetermined value in the ISO bracket shooting mode will be described with reference to FIG. .

  FIG. 9 is a flowchart showing a procedure for setting the imaging sensitivity in the ISO bracket shooting mode when the temperature in the vicinity of the solid-state imaging device 15 is equal to or higher than a predetermined value.

  In step S101, it is determined whether all of the AF mode selection SW 118, the photometry mode selection SW 119, and the drive mode selection SW (DR mode SW) 126 are turned on. If all are turned on, the process proceeds to step S102, and if not all is turned on, the present process is terminated.

  In step S102, according to the operation performed on the main electronic dial 115 by the user, that is, according to the number of rotation clicks and the rotation direction of the main electronic dial 115, the corresponding bracket among the following three modes: The corresponding mode is set for the imaging apparatus.

  That is, there are three bracket-compatible modes: a high sensitivity limit mode, a bracket width priority mode, and a high sensitivity side gain control change mode.

  In the high sensitivity limit mode, when the ISO bracket value is set according to a preset bracket width, the ISO bracket value on the high sensitivity side is limited by the ISO sensitivity that can be used at the temperature near the fixed image sensor 15, and the high sensitivity side When the ISO bracket value exceeds the upper limit value of the ISO sensitivity usable at the temperature, the ISO bracket value on the high sensitivity side is changed to the upper limit value of the ISO sensitivity usable at the temperature. .

  The bracket width priority mode gives priority to the set bracket width. When the ISO bracket value on the high sensitivity side exceeds the upper limit value of the ISO sensitivity that can be used at the temperature near the fixed image sensor 15, the ISO bracket is set. In this mode, the reference center value is shifted to the low sensitivity side to ensure the ISO bracket width on the high sensitivity side.

  The high-sensitivity-side gain control change mode is a mode in which imaging sensitivity control that is normally performed with analog gain is performed by digital processing only on the high-sensitivity side. That is, when trying to cope with high sensitivity with an analog gain, the noise component increases and the quality of the image deteriorates. On the other hand, when digital processing (digital gain) is performed, digital calculation is performed, so that the gradation of an image becomes coarse but noise components are not amplified, and digital processing is useful in terms of noise. In other words, gradation is given priority on the low sensitivity and medium sensitivity sides, and noise reduction is given priority on the high sensitivity side.

  Next, an ISO bracket setting mode for setting in advance to perform ISO bracket shooting will be described with reference to FIGS. 10 and 11.

  ISO bracket shooting is a single release operation, without changing the exposure conditions (without changing the shutter speed or aperture value), and the shooting sensitivity value (solid-state image sensor 15) of the solid-state image sensor 15 for each frame. The image signal output gain adjustment value) is changed to capture a plurality of frames.

  FIG. 10 is a flowchart showing a procedure of ISO bracket setting processing for ISO bracket shooting executed by the CPU 38.

  First, in step S201, it is determined whether or not both the AF mode selection SW 118 and the photometry mode selection SW 119 are ON. If it is determined that both are ON, the process proceeds to step S202, and the ISO bracket setting mode is set. At this time, the screen shown in FIG. 11A is displayed on the external liquid crystal display device 140.

  FIG. 11 is a diagram showing each display screen of the external liquid crystal display device 140.

  In FIG. 11A, the ISO reference center value in the ISO bracket shooting mode is shown at the display position 140a, and the ISO bracket correction amount (gain adjustment amount) is shown as the dot position at the display position 140b. / Unit is 3 stages. The bracket correction amount (gain adjustment amount) is indicated by a 7-segment display at the display position 140c. In the present embodiment, it is indicated that gain adjustment is performed with three different bracket correction amounts (gain adjustment amounts) by displaying three dots at the display position 140b.

  Returning to FIG. 10, in step S <b> 203, the temperature near the solid-state imaging device 15 is measured by the temperature sensor 127.

  In step S204, an upper limit value of the ISO sensitivity that can be used at the temperature measured in step S203 is set. When the temperature is 45 ° C. or higher, noise components of the solid-state imaging device 15 and the image processing circuit in general increase, which adversely affects the photographing result. Therefore, in the present embodiment, the upper limit value of the ISO sensitivity is 1600 when the temperature in the vicinity of the solid-state imaging device 15 is lower than 45 ° C., whereas the upper limit value of the ISO sensitivity is 400 when the temperature is 45 ° C. or higher. Set to

  In step S205, it is determined whether or not the current ISO sensitivity is equal to or lower than the upper limit value of the ISO sensitivity set in step S204. If the current ISO sensitivity is less than or equal to the upper limit value, the process proceeds to step S207, and if greater than the upper limit value, the process proceeds to step S206. In step S206, an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user, the current ISO sensitivity is set to the upper limit value of the ISO sensitivity, and the process proceeds to step S207. .

  In step S207, it is determined whether or not a signal is input from the main electronic dial 115. If it is input, the process proceeds to step S208. If not, the process proceeds to step S209. In step S209, it is determined whether or not a signal is input from the sub electronic dial 116. If it is input, the process proceeds to step S210, and if not, the process proceeds to step S212.

  In step S208, the ISO standard center value is changed according to the input signal from the main electronic dial 115. When the ISO sensitivity setting range is limited according to the detection result of the temperature sensor 127, the ISO sensitivity cannot be set exceeding the limit value.

  On the display screen of the external liquid crystal display device 140 at this time, if the initial value of the ISO reference center value is ISO 200 at the display position 140a shown in FIG. 11, every time the main electronic dial 115 is rotated by one click, 200 → 250. → 320 → 400... 1600 The gain adjustment value of the image signal increases by 1/3 steps. Further, when operated in the reverse rotation direction, the gain adjustment value of the image signal decreases by 1/3 steps, such as 1600 → 1250 → 1000 → 800. The upper limit value of the ISO sensitivity is the upper limit value set in step S204.

  Returning to FIG. 10, in step S210, the amount of change in gain adjustment per click is set to 1/3 EV in accordance with the input signal from the sub electronic dial 116, and the bracket correction amount is determined. When setting the correction amount, the upper limit value of the ISO sensitivity set in step S204 is not considered.

  In the display screen of the external liquid crystal display device 140 at this time, every time the sub electronic dial 116 is rotated by one click from the initial state of FIG. 11A at the display position 140b shown in FIG. Two dot positions indicating the bracket correction amount (gain adjustment amount) diffuse from the reference center value. FIG. 11B shows three dot positions when the sub electronic dial 116 is rotated by one click from the initial state (A). FIG. 11C shows the sub electronic dial 116 from the initial state. A state in which a two-click rotation operation is performed is shown.

  Further, when the sub electronic dial 116 is rotated in the reverse direction, the state in FIG. 11C is sequentially changed from the state in FIG. 11B to the state in FIG.

  The bracket correction amount (gain adjustment amount) displayed at the display position 140c shown in FIG. 11 is also changed from 0.0 → 0.3 → 0 every time the sub electronic dial 116 is rotated by one click corresponding to the dot display. .7 → ... → 3.0, and so on, changing by 1/3 step. Further, when the sub electronic dial 116 is rotated in the reverse direction, it changes from 3.0 → 2.7 → 2.3 →.

  Returning to FIG. 10, when the ISO bracket correction amount (gain adjustment amount) is determined in step S210, the ISO bracket flag is set and the variable N = 0 is stored in the memory in the CPU 38 in step S211. Store it and go to step S212. When this flag is set, ISO bracket shooting described later is performed. That is, when the sub electronic dial 116 is operated in the ISO bracket setting mode and the bracket correction amount is set, ISO bracket shooting can be performed.

  In step S212, it is determined whether or not the AF mode selection SW 118 and the photometry mode selection SW 119 are turned off. If they are not turned off, the process returns to step S203. If they are turned off, the ISO bracket setting mode is terminated. .

  Next, a photographing sequence will be described.

  12 to 17 are flowcharts showing an operation procedure in the imaging apparatus according to the present embodiment.

  First, in step S301, when a power switch (not shown) is turned on (ON), the imaging apparatus enters a standby state for photographing.

  In step S302, a shooting mode is set. The shooting mode can be set by operating the main electronic dial 115 with the shooting mode selection SW 117 turned on.

  In step S303, shooting parameters are set according to the shooting mode set in step S302. In the Av priority mode, the aperture value is set by operating the main electronic dial 115. In the shutter priority mode, the shutter speed is set by operating the main electronic dial 115. In the manual mode, The main electronic dial 115 sets the shutter speed, and the sub electronic dial 116 sets the aperture value. The ISO bracket setting shown in FIGS. 9 and 10 is also performed at this stage.

  In step S304, it is determined whether or not the switch SW (1) 114a is turned on by the half-pressing operation (first stroke operation) of the release button 114. If it is not turned on, the process returns to step S301. If it is turned on, the process proceeds to step S305 and step S307. In step S305, the photometry device 11 performs photometry, and in step S307, the focus detection device 13 performs distance measurement. In step S308, the photographing lens 2 is driven based on the distance measurement result in step S307.

  In step S306, the temperature in the vicinity of the solid-state image sensor 15 is measured by the temperature sensor 127 disposed in the vicinity of the solid-state image sensor 15.

  In step S309, the CPU 36 determines whether the ISO bracket shooting mode is set or another mode is set. When the ISO bracket shooting mode is set, the process proceeds to step 801 shown in FIG. 15, and when the ISO bracket shooting mode is not set, the process proceeds to step S310 in FIG.

  In step S310, it is determined whether the shooting mode is an Av priority mode (aperture priority mode). If it is determined that the mode is the Av priority mode, the exposure parameter in the Av priority mode is determined in step S311. Details of the processing performed in step S311 will be described later with reference to FIG.

  If it is determined in step S310 that the shooting mode is not the Av priority mode, it is determined in step S312 whether or not the shooting mode is a Tv priority mode (shutter priority mode). If it is determined that the Tv priority mode is set, the exposure parameter in the Tv priority mode is determined in step S313. Details of the processing performed in step S313 will be described later with reference to FIG.

  If it is determined in step S312 that the shooting mode is not the Tv priority mode, it is determined in step S314 whether the shooting mode is the program mode. If it is determined that the program mode is selected, exposure parameters in the program mode are determined in step S315. Details of the processing performed in step S315 will be described later with reference to FIG.

  If it is determined in step S314 that the shooting mode is not the program mode, since the shooting mode is the manual mode, the exposure parameter in the manual mode is determined in step S317. Details of the processing performed in step S317 will be described later with reference to FIG.

  As described above, the exposure parameter is determined regardless of which mode is selected. The exposure parameters determined here include a Tv value (target exposure time) and an Av value (target aperture value).

  Next, in step S318, it is determined whether or not the switch SW (2) 114b is turned on by the full press operation (second stroke operation) of the release switch 114. If it is turned on, the process proceeds to step S319. If it is not turned on, the process returns to step S304.

  In step S319, the CPU 38 determines which of the electronic shutter mode and the mechanical shutter mode is set as the shutter control mode. When the electronic shutter mode is set, the process proceeds to step S321 in FIG. 14, and when the mechanical shutter mode is set, the process proceeds to step S325 in FIG.

  If the electronic shutter mode is set, in step S321, the control circuit 36 outputs a leading blade travel start signal to the mechanical shutter device 14 based on the exposure control value sent from the CPU 38, and the leading blade group 14a. After starting driving (opening the front curtain), the process proceeds to the next step S322.

  After the leading blade group 14a is completely opened, in step S322, the control circuit 36 operates the solid-state imaging device 15 to start the charge accumulation operation, and is determined based on the exposure control value sent from the CPU 38. After controlling the charge accumulation time based on the Tv value, the process proceeds to the next step S323.

  In step S323, the control circuit 36 outputs a trailing blade travel start signal to the mechanical shutter device 14 in accordance with the timing of the completion of charge accumulation, and starts driving the trailing blade group 14b to block the solid-state imaging device 15 from light. After (second curtain shielding), the process proceeds to step S330.

  On the other hand, when the mechanical shutter mode is set, in step S325, the solid-state imaging device 15 is operated to start the charge accumulation operation, and in step S326, a leading blade travel start signal is output to the mechanical shutter device 14. After starting the driving of the front blade group 14a (opening the front curtain), the solid-state image sensor 15 is exposed in the next step S327.

  In step S328, the control circuit 36 outputs a rear blade travel start signal to the mechanical shutter device 14 based on the Tv value determined based on the exposure control value sent from the CPU 38, and starts driving the rear blade group 14b. Thus, the exposure operation to the solid-state imaging device 15 by the leading blade group 14a and the trailing blade group 14b is finished (rear curtain shielding).

  In the next step S329, the solid-state imaging device 15 continues the charge value accumulation operation after the trailing blade traveling of the mechanical shutter device 14 is completed, and removes the influence of smear caused by the incidence of excessive light during exposure. Therefore, before the signal charge accumulated in the photoelectric conversion element of the solid-state imaging device 15 is transferred to the vertical transfer CCD, the smear component leaked into the vertical transfer CCD is read out (vertical transfer) and swept away. Thereafter, the process proceeds to step S330.

  In step S330, the solid-state imaging device 15 finishes the charge accumulation operation, transfers the signal charge accumulated in the photoelectric conversion element to the vertical transfer CCD, and performs normal readout which is a signal charge readout operation. Next, image processing is performed in step S331, and after the image is recorded in the memory card 34 in the next step S332, this processing operation is terminated.

  Next, the ISO bracket photographing process after step S801 shown in FIGS. 15 to 17 will be described.

  In step S801, it is determined whether or not the shooting mode is an Av priority mode. If it is determined that the Av priority mode is selected, the exposure parameter in the Av priority mode is determined in step S803. Step S803 performs the same process as step S311 in FIG. 13, and details of the process performed in step S803 will be described later with reference to FIG.

  If it is determined in step S801 that the mode is not the Av priority mode, it is determined in step S802 whether the shooting mode is the Tv priority mode. If it is determined that the Tv priority mode is selected, the exposure parameter in the Tv priority mode is determined in step S804. Step S804 performs the same process as step S313 in FIG. 13, and details of the process performed in step S804 will be described later with reference to FIG.

  If it is determined in step S802 that the mode is not the Tv priority mode, the shooting mode is set to the program mode. Therefore, in step S805, the exposure parameter in the program mode is determined. Step S805 performs the same process as step S315 in FIG. 13, and details of the process performed in step S805 will be described later with reference to FIG.

  As described above, the exposure parameter is determined regardless of which mode is selected. The exposure parameters determined here include a Tv value (target exposure time) and an Av value (target aperture value).

  Next, in step S806, it is determined whether or not the switch SW (2) 114b is turned on by the full press operation (second stroke operation) of the release switch 114. If not, the process proceeds to step S807, where it is determined whether or not a user instruction for interrupting ISO bracket shooting has been issued. If the user instruction has been issued, the process ends. If not, the process returns to step S806.

  If it is determined in step S806 that the switch SW (2) 114b is on, the process proceeds to step S808, and the value of the variable N is checked to determine what frame is being executed in bracket shooting. To do. If N = 0, the process proceeds to step S809. When N = 1, the process proceeds to step S811. When N = 2, the process proceeds to step S810.

  In step S809, the ISO sensitivity is set to the ISO bracket value on the low sensitivity side so that underexposure shooting is performed.

  Specifically, when the temperature measurement result in step S306 in FIG. 12 is less than 45 ° C., the ISO bracket value on the low sensitivity side is the ISO reference center value set in step S208 in FIG. 10 and step S210. Determined by the bracket correction amount set in.

  When the bracket support mode is the high sensitivity limit mode, even when the temperature measurement result in step S306 is 45 ° C. or higher, in step S809, which is the setting of the ISO bracket value on the low sensitivity side, the ISO sensitivity is as shown in FIG. It is determined by the ISO reference center value set in step S208 and the bracket correction amount set in step S210.

  When the bracket support mode is the bracket width priority mode, when the ISO reference center value is shifted to the low sensitivity side in the setting of the ISO bracket value on the high sensitivity side in step S810 to be described later, the ISO bracket on the low sensitivity side is also set in step S809. The value is shifted to the low sensitivity side. At this time, an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In step S810, the ISO sensitivity is set to the ISO bracket value on the high sensitivity side so that overexposure shooting is performed.

  Specifically, when the temperature measurement result in step S306 in FIG. 12 is less than 45 ° C., the ISO bracket value on the high sensitivity side is the ISO reference center value set in step S208 in FIG. 10 and step S210. Determined by the bracket correction amount set in.

  When the bracket support mode is the high sensitivity limit mode, when the temperature measurement result in step S306 is 45 ° C. or higher, and the ISO bracket value on the high sensitivity side exceeds the upper limit of the ISO sensitivity that can be used at high temperatures, The ISO bracket value on the high sensitivity side is changed to the upper limit value. In the present embodiment, the upper limit value is ISO400. When the ISO bracket width (bracket correction amount (gain adjustment amount)) on the high sensitivity side is limited as described above, an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to the user. Give a warning.

  When the bracket support mode is the bracket width priority mode, when the temperature measurement result in step S306 is 45 ° C. or higher, the ISO sensitivity (ISO bracket value) on the high sensitivity side with the set ISO bracket width is fixed image sensor 15. If the ISO sensitivity range that can be used at a near temperature is exceeded, the ISO bracket reference center value is shifted to the low sensitivity side so that the ISO sensitivity (ISO bracket value) on the high sensitivity side becomes the upper limit of the ISO sensitivity range. To do. Along with this shift, the ISO sensitivity at the time of standard exposure and under exposure of ISO bracket shooting is also shifted by the same amount as the ISO sensitivity shift amount at the time of overexposure. Further, an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In addition, when the bracket support mode is the high sensitivity side gain control change mode, when the temperature measurement result in step S306 is 45 ° C. or higher, the ISO sensitivity (ISO bracket value) on the high sensitivity side is set with the set ISO bracket width. When the ISO sensitivity range that can be used at the temperature near the fixed imaging element 15 is exceeded, the imaging sensitivity control on the high sensitivity side is performed by digital processing (digital gain change). That is, normally, the gain amplification circuit in the analog signal processing circuit 20 amplifies the imaging signal, and the digital signal processing circuit 48 in the main signal processing circuit 24 performs sensitivity amplification by arithmetic processing.

  In step S811, the ISO sensitivity is set to the medium sensitivity side (standard) so that exposure standard shooting is performed.

  When the temperature measurement result in step S306 in FIG. 12 is less than 45 ° C., the ISO bracket value on the medium sensitivity side is the ISO reference center value set in step S208 in FIG.

  When the bracket support mode is the high sensitivity limit mode, the ISO bracket value on the medium sensitivity side is the ISO reference center value set in step S208 of FIG. 10 even when the temperature measurement result in step S306 is 45 ° C. or higher. .

  When the bracket support mode is the bracket width priority mode, in step S811, if the ISO bracket value on the high sensitivity side in step S810 is shifted, the ISO bracket value is also shifted on the medium sensitivity side. At this time, an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  Next, the processing from step S812 shown in FIG. 16 to step S825 shown in FIG. 17 is the same as the processing from step S319 shown in FIG. 13 to step S332 shown in FIG. .

  In step S826 in FIG. 17, a variable N for counting the number of times of bracket shooting is set to N = N + 1.

  In step S827, it is determined whether or not the value of the variable N incremented in step S826 is 3. When the variable N = 3, the bracket shooting sequence is finished, and the process proceeds to step S828. If the variable N is not 3, the process returns to step S806 in FIG.

  In step S828, after the bracket execution flag is canceled, this processing operation is terminated.

  FIG. 18 is a flowchart showing the procedure of the shooting parameter determination process executed in the Av priority mode, showing the detailed contents of step S311 in FIG. 13 and step S803 in FIG.

  In step S402, an appropriate shutter speed (Tv value) is calculated based on the temperature photometric result of the temperature sensor 127 in step S305 of FIG. 12, and the ISO sensitivity and Av value set in step S303.

  In step S403, the shutter control mode is selected with reference to FIG. 8 based on the temperature measurement result of the temperature sensor 127 and the shutter speed calculated in step S402. This will be described in detail below.

  When the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed calculated in step S402 is higher than 1/30 seconds, the shutter control mode is set to the electronic shutter control mode, and the process proceeds to step S408. Return to the sequence.

  If the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed calculated in step S402 is lower than 1/30 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S408. To return to the original sequence.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed calculated in step S402 is lower than 1/500 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S408. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed calculated in step S402 is higher than 1/500 seconds, image degradation such as noise and smear will occur in the captured image if shooting is continued as it is. Therefore, the process proceeds to step S404, where an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In step S405, it is determined whether or not the release SW (1) 114a is turned on. If it is on, it is determined that the photographer has selected to continue shooting, and the process proceeds to step S406. If the release SW (1) 114a is off, it is determined that the photographer has selected shooting interruption, and shooting is interrupted (S407).

  In step S406, the ISO sensitivity is lowered so that the shutter speed is lower than 1/500 second so that the shutter control mode can be set to the mechanical shutter control mode. In addition, the display content displayed on the LCD monitor device 120 is changed.

  By lowering the ISO sensitivity and selecting the mechanical shutter control mode, the amplification of the noise component due to the increase in ISO sensitivity is suppressed, and the smear component of the CCD transfer path is discharged, and imaging with less image noise is performed. Can do.

  In the ISO bracket shooting mode, if the ISO sensitivity is changed in this step, the ISO sensitivity serving as a reference for ISO bracket shooting is changed.

  After execution of step S406, the process proceeds to step S408 and returns to the original operation procedure.

  FIG. 19 is a flowchart showing the procedure of the shooting parameter determination process executed in the Tv priority mode, showing the detailed contents of step S313 in FIG. 13 and step S804 in FIG.

  In step S502, an appropriate aperture value (Av value) is calculated based on the result of temperature photometry by the temperature sensor 127 in step S305 in FIG. 12 and the ISO sensitivity and Tv value set in step S303 in FIG.

  In step S503, the shutter control mode is selected with reference to FIG. 8 based on the temperature measurement result by the temperature sensor 127 and the shutter speed (Tv value) set in step S303. This will be described in detail below.

  If the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed set in step S303 is higher than 1/30 seconds, the shutter control mode is set to the electronic shutter control mode, and the process proceeds to step S508. Return to the operation procedure.

  If the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed set in step S303 is lower than 1/30 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S508. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed set in step S303 is lower than 1/500 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S508. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed set in step S303 is higher than 1/500 seconds, image degradation such as noise and smear will occur in the captured image if shooting is continued as it is. Therefore, the process proceeds to step S504, where an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In the next step S505, it is determined whether or not the release SW (1) 114a is turned on. If it is on, it is determined that the photographer has selected to continue shooting, and the process proceeds to step S506. If the release SW (1) 114a is off, it is determined that the photographer has selected to interrupt shooting, and shooting is interrupted (S507).

  In step 506, the ISO sensitivity is lowered so that the shutter speed is lower than 1/500 second so that the shutter control mode can be set to the mechanical shutter control mode. If necessary, the aperture value is recalculated. In addition, the display content displayed on the LCD monitor device 120 is changed.

  By lowering the ISO sensitivity and selecting the mechanical shutter control mode, the amplification of the noise component due to the increase in ISO sensitivity is suppressed, and the smear component of the CCD transfer path is discharged, and imaging with less image noise is performed. Can do.

  In the ISO bracket shooting mode, if the ISO sensitivity is changed in this step, the ISO sensitivity serving as a reference for ISO bracket shooting is changed.

  After execution of step S506, the process proceeds to step S508 and returns to the original operation procedure.

  FIG. 20 is a flowchart showing the procedure of the shooting parameter determination process executed in the program mode, showing the detailed contents of step S315 in FIG. 13 and step S805 in FIG.

  In step S602, an appropriate shutter speed (Tv value) and aperture value (Av value) based on the result of temperature photometry by the temperature sensor 127 in step S305 in FIG. 12 and the ISO sensitivity set in step S303 in FIG. Is calculated.

  In step S603, the shutter control mode is selected with reference to FIG. 8 based on the measurement result by the temperature sensor 127 and the shutter speed calculated in step S602. This will be described in detail below.

  When the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed calculated in step S602 is higher than 1/30 seconds, the shutter control mode is set to the electronic shutter control mode, and the process proceeds to step S608. Return to the operation procedure.

  When the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed calculated in step S602 is lower than 1/30 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S608. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed calculated in step S602 is lower than 1/500 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S608. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed calculated in step S602 is higher than 1/500 seconds, image degradation such as noise and smear occurs in the captured image if shooting is continued as it is. In step S604, an alarm sound is generated from the buzzer 128, or a blinking display is performed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In the next step S605, it is determined whether or not the release SW (1) 114a is on. If it is on, it is determined that the photographer has selected to continue shooting, and the process proceeds to step S606. If the release SW (1) 114a is off, it is determined that the photographer has selected the interruption of shooting, and shooting is interrupted (S607).

  In step S606, the program shift is automatically performed so that the shutter speed is lower than 1/500 second so that the shutter control mode can be set to the mechanical shutter control mode. If the aperture value and shutter speed do not become settable values only by program shift, the ISO sensitivity is lowered so that a lower shutter speed can be selected, thereby changing the shutter control mode to the mechanical shutter control mode. Make it configurable. In addition, the aperture value is recalculated. In addition, the display content displayed on the LCD monitor device 120 is changed.

  By lowering the ISO sensitivity and selecting the mechanical shutter control mode, the amplification of the noise component due to the increase in ISO sensitivity is suppressed, and the smear component of the CCD transfer path is discharged, and imaging with less image noise is performed. Can do.

  In the ISO bracket shooting mode, if the ISO sensitivity is changed in this step, the ISO sensitivity serving as a reference for ISO bracket shooting is changed.

  After execution of step S606, the process proceeds to step S608 and returns to the original operation procedure.

  FIG. 21 is a flowchart showing the procedure of the shooting parameter determination process executed in the manual mode, showing the detailed contents of step S317 in FIG.

  In step S702, the shutter control mode is selected with reference to FIG. 8 based on the shutter speed (Tv value) set in step S303 of FIG. This will be described in detail below.

  When the temperature measurement result by the temperature sensor 127 is less than 45 ° C. and the shutter speed set in step S303 is higher than 1/30 seconds, the shutter control mode is set to the electronic shutter control mode, and the process proceeds to step S707. Return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is less than 45 ° C. and the shutter speed set in step S303 is lower than 1/30 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S707. To return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed set in step S303 is lower than 1/500 seconds, the shutter control mode is set to the mechanical shutter control mode, and the process proceeds to step S707. Return to the original operation procedure.

  If the measurement result of the temperature sensor 127 is 45 ° C. or higher and the shutter speed set in step S303 is higher than 1/500 seconds, image degradation such as noise and smear will occur in the captured image if shooting is continued as it is. Accordingly, the process proceeds to step S703, where an alarm sound is generated from the buzzer 128 or blinking is displayed on the external liquid crystal display device 140 or the like to give a warning to the user.

  In the next step S704, it is determined whether or not the release SW (1) 114a is on. If it is on, it is determined that the photographer has selected to continue shooting, and the process proceeds to step S707. If the release SW (1) 114a is off, it is determined that the photographer has selected the interruption of shooting, and shooting is interrupted (S706).

  In step S705, the shutter speed is reduced so that the shutter speed is lower than 1/500 seconds. Further, the ISO sensitivity is lowered according to the amount of reduction in shutter speed. This is to make the exposure amount the same as that before changing the shutter speed. Thereby, the shutter control mode can be set to the mechanical shutter control mode. In addition, the aperture value is recalculated. In addition, the display content displayed on the LCD monitor device 120 is changed.

  By lowering the ISO sensitivity and selecting the mechanical shutter control mode, the amplification of the noise component due to the increase in ISO sensitivity is suppressed, and the smear component of the CCD transfer path is discharged, and imaging with less image noise is performed. Can do.

  In the ISO bracket shooting mode, if the ISO sensitivity is changed in this step, the ISO sensitivity serving as a reference for ISO bracket shooting is changed.

  After execution of step S705, the process proceeds to step S707 and returns to the original operation procedure.

  As described above, in the imaging apparatus according to the present embodiment, by changing the imaging sensitivity, it is possible to obtain an image with little image quality degradation even when the imaging apparatus is at a high temperature.

[Other Embodiments]
An object of the present invention is to supply a storage medium storing software program codes for realizing the functions of the above-described embodiments to a system or apparatus, and a computer (or CPU, MPU, etc.) of the system or apparatus. It is also achieved by reading and executing the program code stored in the storage medium.

  In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium and program storing the program code constitute the present invention.

  The storage medium for supplying the program code is, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW. DVD + RW, magnetic tape, nonvolatile memory card, ROM, etc. can be used.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) or the like running on the computer based on the instruction of the program code. Includes a case where part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

  Further, after the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. This includes the case where the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

It is a block diagram which shows the internal structure of the imaging device in one embodiment of this invention. It is a sectional side view which shows the structure of this imaging device. It is an external appearance top view of this imaging device. It is an external appearance rear view of this imaging device. It is a figure which shows the imaging | photography sequence at the time of mechanical shutter control mode. It is a figure which shows the imaging | photography sequence at the time of electronic shutter control mode. It is a figure which shows the control sequence of the mechanical shutter apparatus at the time of the electronic shutter control mode in FIG. It is a figure which shows the area | region where electronic shutter control mode and mechanical shutter control mode are performed in the imaging device which concerns on this Embodiment along shutter second time. It is a flowchart which shows the procedure of the setting process of the imaging sensitivity in the ISO bracket imaging | photography mode in case the temperature of the solid-state image sensor 15 vicinity is more than predetermined value. It is a flowchart which shows the procedure of the ISO bracket setting process for ISO bracket imaging | photography performed with CPU38. It is a figure which shows each display screen of an external liquid crystal display device. It is a flowchart (1/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart (2/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart (3/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart (4/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart (5/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart (6/6) which shows the operation | movement procedure in the imaging device of this Embodiment. It is a flowchart which shows the procedure of the imaging | photography parameter determination process performed in the Av priority mode which shows the detailed content of step S311 of FIG. 13, and step S803 of FIG. It is a flowchart which shows the procedure of the imaging parameter determination process performed at the time of Tv priority mode which shows the detailed content of step S313 of FIG. 13, and step S804 of FIG. FIG. 16 is a flowchart showing a procedure of photographing parameter determination processing executed in a program mode, showing detailed contents of step S315 of FIG. 13 and step S805 of FIG. It is a flowchart which shows the procedure of the imaging | photography parameter determination process performed in the manual mode which shows the detailed content of step S317 of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image pick-up device main body 2 Shooting lens 3 Imaging lens 4 Lens drive device 5 Aperture blade group 6 Aperture drive device 7 Main mirror 8 Focusing screen 9 Optical member (penta dach prism)
DESCRIPTION OF SYMBOLS 10 Eyepiece apparatus 11 Photometry apparatus 12 Submirror 13 Focus detection apparatus 14 Mechanical shutter apparatus 14a Lead blade group 14b Rear blade group 15 Solid-state image sensor (imaging means)
16 Electric board 20 Analog signal processing circuit 22 A / D converter 24 Main signal processing circuit (imaging sensitivity setting means)
26 memory 28 D / A converter 32 compression / decompression circuit 34 memory card 36 control circuit (imaging sensitivity bracket photographing means)
38 CPU (imaging sensitivity limiting means, imaging sensitivity bracket imaging means, bracket width setting means, imaging sensitivity changing means)
40 Gain Adjustment Circuit 42 Offset Circuit 46 Histogram Generation Circuit 48 Digital Signal Processing Circuit 50 External Video Output 127 Temperature Sensor (Temperature Measurement Means)
120 LCD monitor device

Claims (23)

Imaging means for imaging a subject;
Temperature measuring means for measuring the temperature in the vicinity of the imaging means;
Imaging sensitivity setting means for setting imaging sensitivity in the imaging means;
An imaging apparatus comprising: an imaging sensitivity limiting unit that limits a range of imaging sensitivity that can be set by the imaging sensitivity setting unit based on a measurement result by the temperature measuring unit.   2. The imaging according to claim 1, wherein the imaging sensitivity limiting unit sets an upper limit value of imaging sensitivity that can be set by the imaging sensitivity setting unit when the temperature measured by the temperature measuring unit is larger than a predetermined value. apparatus.   The imaging sensitivity limiting means is set by the imaging sensitivity setting means when the temperature measured by the temperature measuring means is greater than a predetermined temperature and the imaging sensitivity set by the imaging sensitivity setting means is greater than or equal to a predetermined sensitivity. The imaging apparatus according to claim 1, further comprising imaging sensitivity changing means for reducing the imaging sensitivity. With a single release operation, imaging sensitivity bracket imaging means for performing imaging a plurality of times by changing the imaging sensitivity in the imaging means stepwise,
Bracket width setting means for setting a bracket width that is an amount of change in imaging sensitivity in photographing by the imaging sensitivity bracket photographing means;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting means does not fall within the imaging sensitivity range restricted by the imaging sensitivity restriction means, the imaging sensitivity is set to fall within the range. The imaging apparatus according to claim 1, further comprising: an imaging sensitivity changing unit that changes the imaging sensitivity set by the sensitivity setting unit. With a single release operation, imaging sensitivity bracket imaging means for performing imaging a plurality of times by changing the imaging sensitivity in the imaging means stepwise,
Bracket width setting means for setting a bracket width that is an amount of change in imaging sensitivity in photographing by the imaging sensitivity bracket photographing means;
The imaging apparatus according to claim 1, further comprising bracket width limiting means for limiting a bracket width set by the bracket width setting means when the temperature measured by the temperature measuring means is larger than a predetermined value. . With a single release operation, imaging sensitivity bracket imaging means for performing imaging a plurality of times by changing the imaging sensitivity in the imaging means stepwise,
Bracket width setting means for setting a bracket width that is an amount of change in imaging sensitivity in photographing by the imaging sensitivity bracket photographing means;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting unit exceeds the upper limit value of the imaging sensitivity range limited by the imaging sensitivity limiting unit, imaging is performed by changing the gain by digital calculation. The imaging apparatus according to claim 1, further comprising an imaging sensitivity correction unit that performs sensitivity correction. With a single release operation, imaging sensitivity bracket imaging means for performing imaging a plurality of times by changing the imaging sensitivity in the imaging means stepwise,
Bracket width setting means for setting a bracket width that is an amount of change in imaging sensitivity in photographing by the imaging sensitivity bracket photographing means;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting unit exceeds the upper limit value of the imaging sensitivity range limited by the imaging sensitivity limiting unit, the imaging sensitivity bracket value is The imaging apparatus according to claim 1, further comprising bracket value changing means for changing to an upper limit value.   2. The imaging apparatus according to claim 1, further comprising warning means for giving a warning when the imaging sensitivity set by the imaging sensitivity setting means is changed.   The imaging apparatus according to claim 1, further comprising an exposure value setting unit that resets an exposure setting value other than the imaging sensitivity when the imaging sensitivity set by the imaging sensitivity setting unit is changed. Electronic shutter means for controlling the accumulation time of charges accumulated in a solid-state imaging device included in the imaging means;
Mechanical shutter means for mechanically controlling the incident time of the subject luminous flux to the imaging means;
10. A shutter selection operation unit that selects and operates one of the electronic shutter unit and the mechanical shutter unit based on a measurement result by the temperature measurement unit. An imaging apparatus according to claim 1.   When the temperature measured by the temperature measuring means is higher than a predetermined temperature and the exposure time to be exposed is shorter than the predetermined time, the mechanical shutter means is selected and the exposure time is changed from the outside 11. The image pickup apparatus according to claim 10, further comprising shutter selection / recalculation means for recalculating the exposure setting value. Imaging means for imaging a subject;
Temperature measuring means for measuring the temperature in the vicinity of the imaging means;
Electronic shutter means for controlling the accumulation time of charges accumulated in a solid-state imaging device included in the imaging means;
Mechanical shutter means for mechanically controlling the incident time of the subject luminous flux to the imaging means;
An image pickup apparatus comprising: a shutter selection operation unit that selects and operates one of the electronic shutter unit and the mechanical shutter unit based on a measurement result of the temperature measurement unit.   When the temperature measured by the temperature measuring means is higher than a predetermined temperature and the exposure time to be exposed is shorter than the predetermined time, the mechanical shutter means is selected and the exposure time is changed from the outside 13. The imaging apparatus according to claim 12, further comprising shutter selection / recalculation means for recalculating the exposure setting value. In an imaging sensitivity control method applied to an imaging apparatus including an imaging unit that images a subject and a temperature measurement unit that measures a temperature in the vicinity of the imaging unit,
An imaging sensitivity setting step for setting imaging sensitivity in the imaging means;
An imaging sensitivity control method, comprising: an imaging sensitivity limiting step for limiting an imaging sensitivity range set by the imaging sensitivity setting step based on a measurement result by the temperature measuring means.   15. The imaging according to claim 14, wherein the imaging sensitivity limiting step sets an upper limit value of imaging sensitivity that can be set by the imaging sensitivity setting step when the temperature measured by the temperature measuring unit is larger than a predetermined value. Sensitivity control method.   The imaging sensitivity limiting step is set by the imaging sensitivity setting step when the temperature measured by the temperature measuring unit is greater than a predetermined temperature and the imaging sensitivity set by the imaging sensitivity setting step is equal to or higher than a predetermined sensitivity. The imaging sensitivity control method according to claim 14, further comprising an imaging sensitivity changing step of reducing the imaging sensitivity. In a single release operation, an imaging sensitivity bracket imaging step of performing imaging a plurality of times by changing the imaging sensitivity of the imaging means stepwise,
A bracket width setting step for setting a bracket width that is a change amount of the imaging sensitivity in the imaging performed by the imaging sensitivity bracket imaging step;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting step does not fall within the imaging sensitivity range restricted by the imaging sensitivity restriction step, the imaging sensitivity is set to fall within the range. The imaging sensitivity control method according to claim 14, further comprising: an imaging sensitivity changing step of changing the imaging sensitivity set by the sensitivity setting step. In a single release operation, an imaging sensitivity bracket imaging step of performing imaging a plurality of times by changing the imaging sensitivity of the imaging means stepwise,
A bracket width setting step for setting a bracket width that is a change amount of the imaging sensitivity in the imaging performed by the imaging sensitivity bracket imaging step;
The imaging sensitivity according to claim 14, further comprising: a bracket width limiting step for limiting a bracket width set by the bracket width setting step when the temperature measured by the temperature measuring means is larger than a predetermined value. Control method. In a single release operation, an imaging sensitivity bracket imaging step of performing imaging a plurality of times by changing the imaging sensitivity of the imaging means stepwise,
A bracket width setting step for setting a bracket width that is a change amount of the imaging sensitivity in the imaging performed by the imaging sensitivity bracket imaging step;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting step exceeds the upper limit value of the imaging sensitivity range limited by the imaging sensitivity limiting step, imaging is performed by changing the gain by digital calculation. The imaging sensitivity control method according to claim 14, further comprising: an imaging sensitivity correction step for performing sensitivity correction. In a single release operation, an imaging sensitivity bracket imaging step of performing imaging a plurality of times by changing the imaging sensitivity of the imaging means stepwise,
A bracket width setting step for setting a bracket width that is a change amount of the imaging sensitivity in the imaging performed by the imaging sensitivity bracket imaging step;
When the imaging sensitivity bracket value determined by the bracket width set by the bracket width setting step exceeds the upper limit value of the imaging sensitivity range limited by the imaging sensitivity limitation step, the imaging sensitivity bracket value is The imaging sensitivity control method according to claim 14, further comprising: a bracket value changing step of changing to an upper limit value. Imaging means for imaging a subject, temperature measuring means for measuring the temperature in the vicinity of the imaging means, electronic shutter means of a system for controlling the accumulation time of charges accumulated in a solid-state imaging device included in the imaging means, In a shutter control method applied to an image pickup apparatus provided with a mechanical shutter means of a system for mechanically controlling an incident time of a subject light beam on the image pickup means,
A shutter control method comprising: a shutter selection operation step of selecting and operating one of the electronic shutter unit and the mechanical shutter unit based on a measurement result by the temperature measuring unit. In a program for causing a computer to execute an imaging sensitivity control method applied to an imaging device including an imaging unit that images a subject and a temperature measurement unit that measures a temperature in the vicinity of the imaging unit.
An imaging sensitivity setting step for setting imaging sensitivity in the imaging means;
An imaging sensitivity limiting step for limiting a range of imaging sensitivity set by the imaging sensitivity setting step based on a measurement result by the temperature measuring means. Imaging means for imaging a subject, temperature measuring means for measuring the temperature in the vicinity of the imaging means, electronic shutter means of a system for controlling the accumulation time of charges accumulated in a solid-state imaging device included in the imaging means, In a program for causing a computer to execute a shutter control method applied to an image pickup apparatus including a mechanical shutter means for mechanically controlling an incident time of a subject light beam on the image pickup means,
A program comprising: a shutter selection operation step of selecting and operating one of the electronic shutter unit and the mechanical shutter unit based on a measurement result by the temperature measuring unit.

Images