JP2009130887A - Imaging apparatus and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus which enables a photographer to perform observation without feeling pains and suppresses the consumption of power of a power supply battery as much as possible in the long period exposure of valve photographing or the like, and to provide a method of controlling the imaging apparatus. <P>SOLUTION: The imaging apparatus includes an imaging unit 291 for repeatedly imaging an object image in a set cycle to output image data during the execution of the valve photographing, an adding operation unit 292 for performing an adding operation with past image data every time the image data is output and generating added images, an image display 296 for displaying the added images, and a sounding unit 298 for performing sounding for the prescribed time interlocked with the updating of image display in the image display 296. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging device and a method for controlling the imaging device, and more particularly to an imaging device capable of displaying a subject image according to the degree of exposure in long-time shooting such as bulb shooting and a method for controlling the imaging device.

  In general, bulb photography is often used when photographing subjects such as the starry sky, fireworks, and night views. However, bulb exposure varies in the appropriate exposure time (time from shutter opening to shutter closing) depending on the object to be photographed and ambient conditions, and the photographer can determine the exposure time without looking at the finished image at his own discretion. Had to decide. Therefore, there is a problem that if the judgment is wrong, the exposure becomes insufficient and the exposure becomes excessive.

Therefore, when a photographed image can be observed in accordance with exposure during bulb photographing or the like, the exposure level can be observed in real time, and the exposure time can be easily determined. For example, Patent Document 1 discloses an imaging apparatus that takes out pixel signals from an imaging element at a predetermined time interval (for example, 1/10 second) during an imaging operation and displays sequentially added images on a liquid crystal monitor. Yes.
JP 2005-117395 A

  According to the imaging apparatus described in Patent Document 1, since the progress of exposure can be confirmed, a large failure can be prevented even in bulb photography. However, bulb photography takes a relatively long time, and there is no change in the display image until the image is updated, so it is painful to watch the display screen during that time.

  The present invention has been made in view of such circumstances, and provides an imaging apparatus and a control method for the imaging apparatus that enable a photographer to observe without pain during long exposure such as bulb photography. With the goal.

  In order to achieve the above object, an image pickup apparatus according to a first aspect of the present invention, during execution of bulb photography, repeatedly captures a subject image at a set cycle and outputs image data, and the image data is output. Each time, an addition calculation unit that performs addition calculation with past image data and generates an addition image, an image display unit that displays the addition image, and update of image display in the image display unit, And a sounding unit for sounding time.

In the imaging device according to a second aspect, in the first aspect, the sound generation unit performs the predetermined sound generation when an image display update period in the image display unit is greater than or equal to a predetermined value.
An imaging apparatus according to a third aspect of the present invention includes a lighting unit that illuminates the image display unit in the first aspect of the invention, and the lighting unit is linked with the update of the image display in a second predetermined manner. During the time, the image display unit is illuminated.

  Furthermore, in the image pickup apparatus according to the fourth invention, in the first invention, the image display unit displays notification information indicating that the bulb photographing is being executed.

  According to a fifth aspect of the present invention, there is provided a control method for an image pickup apparatus, in which a subject image is repeatedly taken at a set cycle during bulb photography, image data is output, and a past image is output each time the image data is output. An addition operation with data is performed, an addition image is generated, the addition image is displayed, and a sound is generated for a predetermined time in conjunction with the update of the image display.

  According to the present invention, it is possible to provide an imaging device and a control method for the imaging device that enable a photographer to observe without pain during long exposure such as bulb photography.

  Hereinafter, a preferred embodiment using a digital single-lens reflex camera to which the present invention is applied will be described with reference to the drawings. FIG. 1 is an external perspective view of a digital single-lens reflex camera according to an embodiment of the present invention as seen from the back.

  This digital single-lens reflex camera is composed of a camera body 200 and an interchangeable lens 100. On the upper surface of the camera body 200, a release button 21, a shooting mode dial 22, an information setting dial 24, a strobe 50, and the like are arranged. The release button 21 has a first release switch that is turned on when the photographer is half-pressed and a second release switch that is turned on when the photographer is fully pressed. When the first release switch (hereinafter referred to as 1R) is turned on, the camera performs photographing preparation operations such as focus detection, focusing of the photographing lens, and photometry of the subject brightness, and the second release switch (hereinafter referred to as 2R). When the camera is turned on, the camera executes a photographing operation for capturing image data of the subject image based on the output of the image sensor 221 (see FIG. 2).

  The shooting mode dial 22 is an operation member configured to be rotatable. By matching a picture display or a symbol representing the shooting mode provided on the shooting mode dial 22 with an index, the program shooting mode (P) and aperture priority are set. Each shooting mode such as shooting mode (A), shutter shooting priority mode (S), manual shooting mode (M), bulb mode (B), etc. can be selected.

  The information setting dial 24 is an operation member configured to be rotatable, and a desired setting value, mode, or the like can be selected by rotating the information setting dial 24 on an information display screen or the like. When the bulb mode is set, the update time of the image display during exposure can be set. The strobe 50 is a pop-up type auxiliary lighting device. By operating an operation button (not shown), the strobe 50 pops up and can irradiate the subject.

  On the rear surface of the camera body 200, there are a liquid crystal monitor 26, a continuous / single shooting button 27, an AE lock button 28, an up cross button 30U, a down cross button 30D, a right cross button 30R, and a left cross button 30L (these buttons). The cross buttons 30U, 30D, 30R, and 30L are collectively referred to as a cross button 30), an OK button 31, a live view display button 33, an enlarge button 34, a menu button 37, and a playback button 38. . The liquid crystal monitor 26 is a display device that performs live view display, reproduces and displays a captured subject image, and displays shooting information and menus. At the time of bulb photographing, an image is displayed based on an image signal acquired by the image sensor 221 during the exposure operation. Any liquid crystal display can be used as long as it can perform these displays.

  The continuous shooting / single shooting button 27 is a continuous shooting mode in which continuous shooting is performed while the release button 21 is fully pressed, and a single shooting mode in which one frame is shot when the release button 21 is fully pressed. This is an operation member for switching. The AE lock button 28 is an operation member for fixing the photometric value. Thus, when the luminance of the object to be photographed is measured and then the AE lock button 28 is operated, the photometric value is retained even if the composition is changed, and photographing can be performed without changing the exposure level.

  The cross button 30 is an operation member for instructing the movement of the cursor in the two-dimensional direction of the X direction and the Y direction on the liquid crystal monitor 26. In addition, when reproducing and displaying the subject image recorded on the recording medium 277, It is also used to select a subject image. In addition to providing four buttons for up, down, left, and right, it is possible to replace with an operation member that can be operated in two dimensions, such as a switch that can detect the operation direction in two dimensions, such as a touch switch. It is. The OK button 31 is an operation member for confirming various items selected by the cross button 30, the control dial 24, or the like.

  The live view display button 33 is an operation button for switching from a display screen for information display or the like to a live view display, or from a live view display to a display screen for information display or the like. The live view display is a mode in which the subject image is displayed on the liquid crystal monitor 26 for observation based on the output of the image sensor 221 for recording the subject image, and the information display is set to display shooting information of the digital single lens reflex camera. Therefore, this mode is displayed on the liquid crystal monitor 26. The enlargement button 34 is an operation member for enlarging and displaying a part of the subject image on the liquid crystal monitor 26, and the enlargement position can be changed by operating the cross button 30 described above.

  The menu button 37 is an operation member for switching to a menu mode for setting various modes of the digital single-lens reflex camera. When the menu mode is selected by operating the menu button 37, a menu screen is displayed on the liquid crystal monitor 26. Is done. The menu screen has a plurality of hierarchical structures. Various items are selected with the cross-shaped button 30, and selection is determined by operating the OK button 31. The playback button 38 is an operation button for instructing the liquid crystal monitor 26 to display a subject image recorded after shooting. The image data of the subject stored in a later-described SDRAM (Synchronous Dynamic Random Access Memory) 267 and recording medium 277 in a compression mode such as JPEG is expanded and displayed.

  A recording medium storage lid 40 is attached to the side surface of the camera body 200 so as to be freely opened and closed. When the recording medium storage lid 40 is opened, a loading slot for the recording medium 277 is provided therein, and the recording medium 277 can be detachably loaded into the camera body 200.

  Next, the overall configuration of the digital single-lens reflex camera mainly including the electric system will be described with reference to FIG. In the present embodiment, the interchangeable lens 100 and the camera body 200 are configured separately and are electrically connected by the communication contact 300, but the interchangeable lens 100 and the camera body 200 can also be configured integrally. . The circuit block of the built-in strobe 50 is omitted in FIG.

  Inside the interchangeable lens 100, a photographing optical system 101 for focus adjustment and focal length adjustment, and a diaphragm 103 for adjusting the aperture amount are arranged. The photographing optical system 101 is driven by a lens driving mechanism 107, and the diaphragm 103 is connected to be driven by a diaphragm driving mechanism 109.

  The lens driving mechanism 107 and the aperture driving mechanism 109 are each connected to a lens CPU 111, and the lens CPU 111 is connected to a communication circuit 273 of the camera body 200 via a communication contact 300. The lens CPU 111 controls the inside of the interchangeable lens 100. The lens CPU 111 controls the lens driving mechanism 107 to perform focusing and zoom driving, and also controls the aperture driving mechanism 109 to perform aperture value control. Further, the lens CPU 111 transmits lens-specific information such as an open aperture value and focal length information of the interchangeable lens 100, and focal length and focal position information detected by an optical system position detection mechanism (not shown) to the camera body 200. To do.

  In the camera body 200, a position tilted by 45 degrees with respect to the optical axis of the lens (the lowered position, the subject image observation position) in order to reflect the subject image to the observation optical system, and a subject image to be guided to the image sensor 221. A movable mirror 201 that can be rotated between the jumped up position (the raised position and the retracted position) is provided. Above the movable mirror 201, a focusing screen 205 for forming a subject image is disposed, and above this focusing screen 205, a pentaprism 207 for horizontally reversing the subject image is disposed.

  An eyepiece lens (not shown) for observing the subject image is arranged on the emission side (right side in FIG. 2) of the pentaprism 207, and the photometric sensor 211 is arranged on the side of the pentaprism 207 so as not to interfere with the observation of the subject image. Has been. The photometric sensor 211 is connected to a photometric processing circuit 241, and the output of the photometric sensor 211 is subjected to processing such as amplification and analog-digital conversion by the photometric processing circuit 241.

  Near the center of the movable mirror 201 described above is a half mirror, and on the back surface of the movable mirror 201, a sub mirror 203 for reflecting subject light transmitted through the half mirror portion to the lower part of the camera body 200 is provided. ing. The sub mirror 203 is rotatable with respect to the movable mirror 201. When the movable mirror 201 is flipped up (the position indicated by a broken line in FIG. 2), the sub mirror 203 is rotated to a position that covers the half mirror portion. When in the observation position (lowering position), it is in an open position with respect to the movable mirror 201 as shown.

  This movable mirror 201 is driven by a movable mirror drive mechanism 239. A focus detection sensor 243 is disposed below the sub mirror 203, and an output of the focus detection sensor 243 is connected to a focus detection processing circuit 245. The focus detection sensor 243 is a known phase difference AF that separates the peripheral light beam of the photographic optical system 101 into two light beams in order to measure the defocus amount of the subject image formed by the photographic optical system 101. It consists of an optical system and a pair of sensors.

A focal plane type shutter 213 for controlling the exposure time is disposed behind the movable mirror 201, and this shutter 213 is driven and controlled by a shutter drive mechanism 237. An imaging element 221 is disposed behind the shutter 213 and photoelectrically converts a subject image formed by the photographing optical system 101 into an electrical signal. The imaging element 211 may be a CCD (Charge Coupled Devices) or a CMOS (Complementary).
Needless to say, a two-dimensional image sensor such as Metal Oxide Semiconductor can be used.

  Between the shutter 213 and the image sensor 221, an infrared cut filter / low pass filter 217, which is an optical filter for removing an infrared light component and a high frequency component from a subject light beam, is disposed.

  The image sensor 221 is connected to the image sensor drive circuit 223, and the image sensor drive circuit 223 reads an image signal from the image sensor 221. The image sensor driving circuit 223 is connected to an ADC (Analogue Digital Converter) 225 that performs analog-digital conversion of an image signal. The output of the ADC 225 is connected to the dark current removal circuit 227. The dark current removal circuit 227 is a circuit for removing dark current generated in the image sensor 221 and corrects image data representing the subject image using the dark current generated in the light-shielding region around the image sensor 221. To do.

The dark current removal circuit 227 is an ASIC (Application Specific
Integrated Circuit Application Specific Integrated Circuit) 250 is connected to a data bus 252 in the circuit. The data bus 252 includes a sequence controller (hereinafter referred to as “body CPU”) 251, an image processing circuit 257, a compression / decompression circuit 259, a video signal output circuit 261, an SDRAM control circuit 265, an input / output circuit 271, and a communication circuit 273. A recording medium control circuit 275, a flash memory control circuit 279, a switch detection circuit 283, and a buzzer 287 are connected.

  The body CPU 251 connected to the data bus 252 controls the operation of this digital single lens reflex camera. The image processing circuit 257 connected to the data bus 252 is a variety of images such as digital amplification (digital gain adjustment processing) of digital image data, color correction, gamma (γ) correction, contrast correction, and live view display image generation. Perform processing. The compression / decompression circuit 259 is a circuit for compressing the image data stored in the SDRAM 267 by a compression method such as JPEG or TIFF, and decompressing the compressed image data. Note that image compression is not limited to JPEG or TIFF, and other compression methods can be applied.

  The video signal output circuit 261 is connected to the liquid crystal monitor 26 via the liquid crystal monitor drive circuit 263. The video signal output circuit 261 is a circuit for converting the image data stored in the SDRAM 267 and the recording medium 277 into a video signal for display on the liquid crystal monitor 26. As shown in FIG. 1, the liquid crystal monitor 26 is disposed on the back surface of the camera body 200. However, the liquid crystal monitor 26 is not limited to the back surface as long as the photographer can observe the image. . A liquid crystal monitor backlight 26 a that illuminates the liquid crystal monitor 26 is disposed on the back side of the liquid crystal monitor 26, and is driven and controlled by a liquid crystal monitor drive circuit 263.

  The SDRAM 267 is connected to the data bus 252 via the SDRAM control circuit 265, and the SDRAM 267 temporarily stores the image data processed by the image processing circuit 257 or the image data compressed by the compression / decompression circuit 259. This is a buffer memory.

  The input / output circuit 271 connected to the image sensor driving circuit 223, the shutter driving mechanism 237, the movable mirror driving mechanism 239, the photometry processing circuit 241, and the focus detection processing circuit 245 is connected to each of the body CPU 251 and the like via the data bus 252. Controls circuit and data input / output.

  The communication circuit 273 connected to the lens CPU 111 via the communication contact 300 is connected to the data bus 252 and exchanges data and communicates control commands with the body CPU 251 and the like. A recording medium control circuit 275 connected to the data bus 252 is connected to the recording medium 277 and controls recording of image data and the like on the recording medium 277 and reading of the image data and the like.

  The recording medium 277 can be loaded with any rewritable recording medium such as an xD picture card (registered trademark), a compact flash (registered trademark), an SD memory card (registered trademark), or a memory stick (registered trademark). And is detachable from the camera body 200. In addition, the hard disk may be configured to be connectable via a communication contact.

  The flash memory control circuit 279 is connected to a flash memory 281, and the flash memory 281 stores a program for controlling the operation of the digital single lens reflex camera, and the body CPU 251 stores the program in the flash memory 281. The digital single lens reflex camera is controlled according to the stored program. Note that the flash memory 281 is an electrically rewritable nonvolatile memory.

  1R switch that detects the first stroke (half press) of the release button 21, 2R switch that detects the second stroke (full press), power switch, menu switch linked to the menu button 37, and linked to the shooting mode dial 22 Various switches 285 including a dial switch, a dial switch interlocked with the information setting dial 24, and various switches interlocked with other operation members are connected to the data bus 252 via the switch detection circuit 283. The buzzer 287 is a sound generation member, and displays a notification by sound when an image is updated during bulb photographing, as will be described later.

  Next, a configuration related to image display during exposure in bulb photography will be described with reference to FIG. The control unit 297 includes a body CPU 251 that controls the entire digital single lens reflex camera. The imaging unit 291 includes the above-described imaging element 221, imaging element drive circuit 223, ADC circuit 225, dark current removal circuit 227, and the like, and outputs image data based on the image signal. The output of the imaging unit 291 is connected to the addition operation unit 294.

  The addition operation unit 294 performs addition operation on images acquired every predetermined time during bulb photographing to generate addition image data. Temporary storage unit 293 is configured by a temporary storage device such as SDRAM 267, temporarily stores the added image data calculated in addition operation unit 294, and stores the added image data already stored in accordance with a control command from control unit 297. The data is supplied to the addition calculation unit 294 and newly added image data is stored again. The addition calculation unit 294 includes a body CPU 251 and an image processing circuit 257, and performs addition calculation between the addition image data already stored in the temporary storage unit 293 and the latest image data in accordance with a control command from the control unit 297. .

  The addition image recording unit 295 is configured by a recording medium such as the recording medium 277 described above, and the final addition image data obtained by the addition operation by the addition operation unit 294 is transferred from the temporary storage unit 293 according to the control command of the control unit 297. Read and store. The image display unit 296 includes the liquid crystal monitor 26, the liquid crystal monitor backlight 26a, the liquid crystal monitor drive circuit 263, and the like, and every time the added image data added by the addition calculating unit 294 is updated and stored in the temporary storage unit 293. Then, it is read from the temporary storage unit 293 and displayed according to the control command of the control unit 297. The sound generation unit 298 is configured by the buzzer 287, and notifies the photographer with a notification sound every time the added image displayed on the image display unit 296 is updated.

  Since it is configured in this way, as the display on the liquid crystal monitor 26 at the time of bulb photographing, firstly, notification information 311a for notifying that bulb photographing has started at the start of bulb exposure is displayed (FIG. 8A). )). When the first update time elapses, the image data is read from the imaging unit 291 and the added image (the first read image data as it is at the first stage) is displayed together with the notification information 311b in FIG. 8B. Is displayed on the liquid crystal monitor 26 (in this example, the update time is 30 seconds). At the same time, a sound (for example, “beep”) notifying the updating of the image is generated from the sound generation unit 298.

  Thereafter, the image data acquired by the imaging unit 291 is sequentially added by the addition operation unit 294 for each set update time, and the added image is displayed on the image display unit 296. Each time the added image is updated, as shown in FIGS. 8C to 8G, the notification information 311c to 311g is displayed in a superimposed manner, and at the same time, the sound generation unit 298 is also notified by the notification sound. . Further, in the stage of FIG. 8B, the exposure time is not sufficient, so the image is dark, but after that, the image gradually changes to a bright image, and when the image is cumulatively added over and over again, FIG. As shown, an overexposed image is displayed. The notification information 311b to 311g displays the elapsed time of bulb photography in addition to the bulb photography being executed.

  Next, details of the operation of the digital single-lens reflex camera according to the embodiment of the present invention will be described with reference to the flowcharts shown in FIGS. FIG. 4 shows a power-on reset operation by the body CPU 251 on the camera body 200 side. When a battery is loaded in the camera body 200, this flow starts, and it is determined whether the power switch of the camera body 200 is on (# 1).

  If the result of the determination is that the power switch is off, it enters a sleep state that is a state of low power consumption (# 3). In this sleep state, interrupt processing is performed only when the power switch is turned on, and processing for turning on the power switch is performed in step # 5 and subsequent steps. Until the power switch is turned on, operations other than power switch interrupt processing are stopped to prevent the power battery from being consumed. In step # 1, if the power switch is on, or if the sleep state is canceled in step # 3, power supply is started (# 5).

  Next, if there is information such as the shooting mode set by the shooting mode dial 22, the ISO sensitivity set by the information setting dial 24, the manually set shutter speed or aperture value, those shooting conditions, and lens information Reading is performed (# 7). The lens information is read from the lens CPU 111 via the communication circuit 273 such as lens-specific information such as the full aperture value and focal length information of the interchangeable lens 100. In this step, if the valve mode is set, this information is read.

  Subsequently, it is determined whether or not the valve mode is set (# 9). Since the shooting mode is read in step # 7, it is determined whether or not the bulb mode is set as the read shooting mode. As a result of the determination, if the bulb mode is not set, photometry / exposure amount calculation is performed (# 11). In this step, the subject brightness is measured by the photometric sensor 211, an exposure amount is calculated, and exposure control values such as a shutter speed and an aperture value are calculated according to the shooting mode and shooting conditions using the exposure amount.

  If the valve mode is set as a result of the determination in step # 9, an update time (cycle for repeatedly outputting image data) is input (# 31). The input of the update time will be described later with reference to FIG. When the input of the update time is finished, the process jumps to step # 13. In the bulb mode, since the shutter 213 is opened and closed by a user operation regardless of photometry, the photometry / exposure amount calculation in step # 11 is not executed.

  Next, shooting information is displayed on the liquid crystal monitor 26 (# 13). The shooting information includes the shooting mode and shooting conditions read in step # 7, and the shutter speed and aperture value exposure control values calculated in step # 11. When the bulb mode is set as the shooting mode, as shown in FIG. 9, a valve mode display 301 and an update time display 302 are displayed on the liquid crystal monitor 26 together with other shooting information.

  Once the shooting information is displayed, it is next determined whether or not the playback switch linked to the playback button 38 is on (# 17). The reproduction mode is a mode in which image data recorded on the recording medium 277 is read and displayed on the liquid crystal monitor 26 when the reproduction button 38 is operated. If the result of determination is that the regeneration switch is on, regeneration operation is executed (# 33).

  If the result of determination in step # 17 is that the playback switch is not on, it is determined whether or not the menu switch linked to the menu button 37 is on (# 19). In this step, it is determined whether the menu button 37 is operated and the menu mode is set. If the result of determination is that the menu switch is on, a menu is displayed on the liquid crystal monitor 26 and menu setting operation is performed (# 35). Various setting operations such as AF mode, white balance, ISO sensitivity setting, and drive mode setting can be performed by the menu setting operation.

  If the result of determination in step # 19 is that the menu switch is not on, it is determined whether or not the release button 21 has been pressed halfway, that is, whether or not the 1R switch is on. If the result of determination is that the 1R switch is on, a shooting operation subroutine for shooting preparation and shooting is executed (# 37). Details of this subroutine will be described later with reference to FIG.

  If the result of determination in step # 21 is that the 1R switch is not on, it is determined whether or not the power switch is on as in step # 1 (# 23). If the result of determination is that the power switch is on, processing returns to step # 7 and the above operation is repeated. On the other hand, if the power switch is not on, the power supply is stopped (# 25), the process returns to step # 3, and the above-described sleep state is entered.

  Next, the update time input operation in step # 31 will be described with reference to FIG. When this subroutine is entered, it is first determined whether or not the information setting dial 24 has been operated in order to input the update time (# 45). If the result of determination is that the information setting dial 24 has not been operated, processing returns to the original routine. On the other hand, if the information setting dial 24 has been operated, the switch detection circuit 283 detects the rotation direction (# 47).

  Subsequently, it is determined whether or not the detected rotation direction is a direction for reducing the update time (# 49). As a result of the determination, if the rotation direction decreases the update time, it is determined whether or not the previous update time has reached the lower limit value (# 51). The lower limit value may be set as appropriate, but may be about 0.1 seconds, for example. If the result of determination is that the lower limit has not been reached, the update time is shortened in a predetermined step in order from the current setting state (# 53).

  As shown in FIG. 9, the update time is displayed as the update display 302 in the shooting information on the liquid crystal monitor 26. Each time the information setting dial 24 is rotated to shorten the update time, for example, If the current setting state is the initial value of 30 seconds, it gradually decreases in a predetermined step from (c) in FIG. 10 toward the lower limit value in (a). This step may be appropriately determined in consideration of usability. When the update time is shortened, the original routine is restored.

  If the result of determination in step # 49 is not decreasing, it is determined whether or not the previous update time has reached the upper limit (# 55). The upper limit value may be set as appropriate. For example, the upper limit value may be 9 minutes as a time period that is not affected by the dark current. If the result of determination is that the upper limit has not been reached, the update time is extended in a predetermined step (# 57). Each time the information setting dial 24 is rotated in a direction to increase the update time, the information setting dial 24 gradually increases in a predetermined step from the current state toward the upper limit value in FIG. When the update time extension ends, the process returns to the original routine. This update time interval is an example and can be changed as appropriate.

  Next, the photographing operation in step # 37 will be described with reference to FIG. This subroutine starts when the 1R switch is turned on. First, the photographing information displayed on the liquid crystal monitor 26 is turned off (# 61). Subsequently, a subroutine for phase difference AF control is executed (# 63). In this subroutine, the focus shift direction and the focus shift amount of the photographing optical system 101 are detected by a known phase difference AF, and the drive control of the optical system drive mechanism 107 is performed based on the focus shift direction and the focus shift amount. The system 101 is focused.

  When the phase difference AF is completed, it is determined whether or not the valve mode is set as in step # 9 (# 65). If the bulb mode is not set as a result of the determination, photometry / exposure amount calculation is performed to determine exposure control values such as shutter speed and aperture value (# 67). On the other hand, if the valve mode is set as a result of the determination, step # 67 is skipped and the process proceeds to step # 69. In the bulb mode, as described above, the opening / closing time of the shutter 213 is determined by the photographer, and photometry and exposure amount calculation are unnecessary.

  Subsequently, it is determined whether the shutter button 21 has been fully pressed, that is, whether the 2R switch is on (# 69). If the result of determination is that the 2R switch is not on, it is determined whether or not the 1R switch is on (# 87). If the result of determination is that the 1R switch is not on, the shooting operation is terminated and processing returns to the original routine. On the other hand, if the result of determination is that the 1R switch is on, processing returns to step # 69 and enters a standby state for detecting the state of the 1R switch and 2R switch.

  If the result of determination in step # 69 is that the 2R switch is turned on, the routine proceeds to step for shooting. First, the movable mirror 201 is retracted (moved to the raised position) (# 71). As a result, the subject light flux by the photographing optical system 101 is guided in the direction of the image sensor 221. Subsequently, the lens CPU 111 is instructed to perform a narrowing operation, and the narrowing operation of the diaphragm 103 is executed (# 73).

  Now that the preparation for entering the normal photographing operation or the bulb photographing operation is completed, the exposure operation is started (# 75). In the exposure, the traveling of the front curtain of the shutter 213 is started and the charge accumulation of the image sensor 221 is started. When the time corresponding to the shutter speed obtained in step # 67 or the shutter speed manually set by the photographer has elapsed, the running of the rear curtain of the shutter 213 is started and the charge accumulation of the image sensor 221 is ended.

  Here, when the bulb mode is set, the shutter 213 is opened while the release button 21 is fully pressed, and during this time, the image sensor 221 repeatedly acquires image data at update time intervals. The added image based on the image data is displayed on the liquid crystal monitor 26 while being updated. Details of this exposure operation will be described later with reference to FIG.

  When the exposure operation ends, an instruction to open the diaphragm 103 is output to the lens CPU 111, the diaphragm 103 is opened (# 77), and the movable mirror 201 is returned to the lowered position (# 79). Subsequently, the image data read from the image sensor 221 and subjected to image processing is recorded on the recording medium 277 (# 81), and the display of the image displayed on the liquid crystal monitor 26 is stopped (# 83). When the image display is stopped, the original routine is restored.

  Next, the exposure operation in step # 75 will be described with reference to FIG. When this subroutine is entered, first, as in step # 9, it is determined whether or not the valve mode is set (# 101). If the valve mode is not set as a result of the determination, a normal shooting mode such as a program shooting mode is executed.

  As a normal shooting mode, first, a timer for measuring the exposure time is started (# 103), and when the shutter 213 is opened, the image sensor 221 starts imaging (# 105). That is, photoelectric conversion of the subject image formed on the image sensor 221 is performed, and signal charge accumulation is started. It is determined whether the exposure time (set time) corresponding to the shutter speed calculated in step # 67 or manually set has elapsed (# 107). As a result of the determination, when the exposure time has elapsed, the shutter 213 is closed and the imaging with the image sensor 221 is stopped (# 109).

  Subsequently, the image signal is read from the image sensor 221 (# 111), and the read image signal is temporarily stored in the SDRAM 267 (# 113). Based on the temporarily stored image signal, the captured image is displayed on the liquid crystal monitor 26 (# 115). When the captured image is displayed, the process returns to the original routine.

  If the valve mode is set as a result of the determination in step # 101, first, the added image storage area prepared in the temporary storage unit 293 is cleared (# 119), and manually input in step # 31. An update time is set (# 120). Subsequently, a timer for updating the display update time is started (# 121), and as in step # 105, the shutter 213 is opened and imaging is started (# 122).

  Subsequently, the display of the bulb shooting notification information 311a as shown in FIG. 8A is started (# 123). That is, when the bulb exposure is started, if the screen is black and nothing is displayed, the photographer becomes anxious about whether or not exposure by bulb photography has started. Therefore, in this embodiment, the photographer can recognize that the exposure operation has started by displaying the notification information 311a. When the display of the notification information is started, next, the liquid crystal backlight 26a is turned on to illuminate the liquid crystal monitor 26 (# 124). Thereby, the display screen of the liquid crystal monitor 26 becomes bright and can be visually recognized.

  Subsequently, the update time measuring timer determines whether or not the update time set in step # 120 has elapsed (# 125). As a result of the determination, if the update time has not elapsed, it is determined whether or not the release button 21 has been fully pressed, that is, whether or not the 2R switch has been turned off (# 151).

  If the result of determination is that the 2R switch is not OFF, it is next determined whether or not image display continues for a predetermined time (# 161). In this step, it is determined whether or not the timer for update time measurement that started the time measuring operation in step # 121 (step # 131 after the second time) has passed a predetermined time, for example, 10 seconds. If the predetermined time has not elapsed as a result of the determination, the process returns to step # 125, and the image display on the liquid crystal monitor 26 and the lighting of the liquid crystal monitor backlight 26a are continued.

  On the other hand, if a predetermined time has passed as a result of the determination, the liquid crystal backlight 26a is turned off (# 163), and the display of the added image on the liquid crystal monitor 26 is turned off (# 165). This is to prevent power consumption, and the addition image is displayed only for a predetermined time at the time of update. In this embodiment, the bulb shooting notification display is always displayed on the liquid crystal monitor 26. However, when the image display is turned off in step # 165, the bulb shooting notification display is also turned off. By turning off the power of the monitor 26 itself, power consumption can be further reduced. When the image display is turned off in step # 165, the process returns to step # 125.

  As a result of the determination in step # 125, when the update time has elapsed, similarly to step # 109 and step # 111, the imaging of the image sensor 221 is stopped while the shutter 213 is open, and the image signal is read (# 127, # 129). Subsequently, 1 is added to the update counter (# 130). The update counter is reset at the same time when the timer is started in step # 121, and is incremented by one every time this step # 130 is passed. By multiplying the count value of the update counter by the update time set in step # 120, the accumulated time after the exposure by bulb photography is started can be obtained. Subsequently, the timer for update time measurement is restarted (# 131), and the image sensor 221 is started to image (# 133).

  Next, the added image data is read from the storage area stored immediately before in the temporary storage unit 293, and the addition operation of this image data and the image data read in step # 129 is performed (# 135). The image data of the added image obtained here is stored in the storage area of the temporary storage unit 293 for storing the added image (# 137).

  When the addition image has been accumulated, the addition image temporarily stored in the temporary storage unit 293 is displayed on the liquid crystal monitor 26 (# 139). Subsequently, the liquid crystal monitor 26 is illuminated by the liquid crystal monitor backlight 26a (# 141). As described above, the image display on the liquid crystal monitor 26 and the illumination by the liquid crystal monitor backlight 26a are turned off and turned off when the image display continues for a predetermined time (# 163, # 165). .

  Next, it is determined whether or not the update time set in step # 120 is 30 seconds or more (# 143). If the setting update time is 30 seconds or more as a result of the determination, the sound generation unit 298 (buzzer 287) emits a notification sound for a predetermined time (for example, 0.3 seconds). By issuing a notification sound, it is possible to notify the photographer that the image has been updated. Here, whether the notification sound is generated or not is switched depending on whether or not the setting update time is equal to or longer than the determination time, because when the update time is short, the sound generation interval of the notification sound is short and it feels noisy. . This determination time is not limited to 30 seconds, and may be changed as appropriate. As a result of the determination in step # 143, if the setting update time is less than 30 seconds, or if a notification sound is generated in step # 145, the process returns to step # 125 and the above-described operation is executed.

  In step # 122, at the initial stage when the imaging operation is started, the notification information 311a is displayed on the liquid crystal monitor 26 as shown in FIG. 8A and is illuminated by the liquid crystal monitor backlight 26a. If it is determined in step # 161 that the predetermined time has elapsed, the illumination by the liquid crystal monitor backlight 26a is turned off.

Next, when it is determined in step # 125 that the update time has elapsed, the captured image is read out, and the image at this time is displayed as shown in FIG. 8B (# 139). If the set time is 30 seconds or more, the sound generation unit 298 generates a notification sound (# 145). Further, the liquid crystal monitor backlight 26a illuminates for a predetermined time (# 141 → # 161).

  Then, whenever it is determined in step # 125 that the update time has elapsed, as shown in FIGS. 8C to 8G, the added images and notification displays 311c to 311g are updated. At the same time, a notification sound is emitted for a predetermined time. In the initial stage, the amount of exposure is not enough at the initial stage, so the screen remains dark, but the screen becomes brighter as the accumulated time becomes longer, so the photographer determined that the brightness was as intended. Bulb shooting is terminated at this point.

  As the notification information 311b to 311g, as shown in FIG. 8, a display indicating that bulb photographing is being executed and a cumulative exposure time of bulb photographing are displayed. In this embodiment, the cumulative exposure time is obtained using the count value of the update counter counted in step # 130 and the set update time. However, the present invention is not limited to this, and the cumulative exposure time at the time of bulb photography is calculated. Of course, it is possible to provide a counter to obtain and display the elapsed time based on this counter.

  Since the photographer releases his hand from the release button 21 when the intended brightness is achieved, if it is determined in step # 151 that the 2R switch has been turned off, the shutter 213 is closed as in step # 127. Imaging is stopped (# 153). That is, the exposure operation is terminated, and then the original routine is returned to.

  As described above, in this embodiment, every time the setting update time elapses (# 125 → Y), the image pickup by the image pickup device 221 is stopped and the image data is output. This image data and the temporary storage unit 293 Addition with the immediately preceding addition image stored in the storage area is performed, and the result is stored. The added image stored in each storage area is updated and displayed on the liquid crystal monitor 26 as shown in FIG. 8 every time the update time elapses.

  In the present embodiment, every time an image is updated, a notification sound is generated by the sound generation unit 298. When this notification sound is generated, the liquid crystal monitor 26 may be observed. Observable without pain. Furthermore, since the liquid crystal monitor backlight 26a is lit only for a predetermined time after the image is updated, it is possible to prevent the power from being consumed. Furthermore, since the notification sound by the sound generation unit 298 is stopped when the setting update time is short, it is possible to prevent the notification sound from being generated at short time intervals.

  In the present embodiment, as the notification information, a display indicating bulb photographing and an elapsed time from the start of bulb photographing are displayed, but the elapsed time may be omitted. In addition, although “bulb exposure” and “BULB” are displayed to indicate that bulb photography has started, the present invention is not limited to this, and other displays such as symbols and pictograms may be used.

  Further, in the present embodiment, when the exposure operation is ended, when imaging is stopped in step # 153 (FIG. 7), the process returns to the original routine. However, at this time, since the signal charge is accumulated in the image sensor 221, the image capturing unit 291 may read this signal, generate an added image, and display the added image.

  Furthermore, in the present embodiment, the addition image is generated when the valve mode is set. However, when the exposure is performed for a long time, for example, when the exposure is performed for a long time, the addition image is displayed. It may be generated and displayed.

  Further, in the present embodiment, when the valve mode is set, the release button 21 is fully pressed, and the shutter is opened until the full press is released, that is, while the 2R switch is on, and the imaging operation is performed. Had gone. However, other than this method, for example, the imaging operation is started when the release button 21 is fully pressed (first release operation), and the imaging operation is continued even when the release button 21 is fully released, and again. The imaging operation may be stopped when the release button 21 is fully pressed (second release operation performed after the first release operation).

  Furthermore, in the present embodiment, the update time is set manually in step # 31. However, the update time is not limited to this. For example, when the brightness is high, the update time is shortened according to the brightness of the subject. On the contrary, when the luminance is low, it is of course possible to automatically set the update time, for example.

Furthermore, in the present embodiment, an example in which a single-lens reflex type is applied as a digital camera has been described. However, the present invention may be a digital camera such as a compact type other than a single-lens reflex type, and may be a mobile phone or a personal digital assistant (PDA). Personal
Of course, a camera built into Digital Assist) may be used. The present invention can be applied to any imaging apparatus capable of photographing at a long time such as a bulb mode.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the gist thereof in the implementation stage. . In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, you may delete some components of all the components shown by embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

It is the external appearance perspective view which looked at the digital single-lens reflex camera concerning one Embodiment of this invention from the back. 1 is a block diagram illustrating an overall configuration of an electric system of a digital single-lens reflex camera according to an embodiment of the present invention. In the digital single-lens reflex camera concerning one Embodiment of this invention, it is the block diagram which extracted and showed the structure relevant to imaging and display, such as a valve mode. It is a flowchart which shows the operation | movement of the power-on reset in one Embodiment of this invention. It is a flowchart which shows the operation | movement of the update time input in one Embodiment of this invention. It is a flowchart which shows the imaging | photography operation | movement in one Embodiment of this invention. It is a flowchart which shows the exposure operation | movement in one Embodiment of this invention. It is a figure which shows the display at the time of valve | bulb mode imaging | photography in one Embodiment of this invention, (a) to (g) shows the display which changes with progress of update time. It is a figure which shows the imaging | photography information display of the digital single-lens reflex camera concerning one Embodiment of this invention. It is a figure which shows the update display of the digital single-lens reflex camera concerning one Embodiment of this invention, (a) to (e) shows the display of each different update time.

Explanation of symbols

21 ... Release button, 22 ... Shooting mode dial, 24 ... Information setting dial, 26 ... LCD monitor, 26a ... LCD monitor backlight, 27 ... Continuous / single-shot button, 28 ... AE lock button, 30 ... Cross button, 30U ... Cross button for up, 30D ... Cross button for down, 30R ... Cross button for right, 30L ... Cross button for left, 31 ... OK button, 33 ... Live view display button, 34 ... Enlarge button, 37 ... Menu button, 38 ... Playback button, 40 ... Media loading lid, 50 ... Strobe , 100 ... Interchangeable lens, 101 ... Imaging optical system, 103 ... Diaphragm, 107 ... Optical system drive mechanism, 109 ... Diaphragm drive mechanism, 111 ... Lens CPU, 200 ... Camera body, 201 ... movable mirror, 203 ... Bmirror, 205 ... focusing screen, 207 ... pentaprism, 211 ... photometric sensor, 213 ... focal plane shutter, 217 ... infrared cut filter / low pass filter, 221 ... imaging device, 223 ... Image sensor drive circuit, 225 ... ADC circuit, 227 ... dark current removal circuit, 237 ... shutter drive mechanism, 239 ... movable mirror drive mechanism, 241 ... photometry processing circuit, 243 ... focus detection sensor, 245 ... focus detection processing circuit, 250 ... ASIC, 251 ... sequence controller (body CPU), 252 ... data bus, 257 ... image processing circuit, 259 ... Compression / decompression circuit, 261 ... Video signal output circuit, 263 ... Liquid crystal monitor drive circuit, 265. SDRAM detection circuit, 267 ... SDRAM, 271 ... input / output circuit, 273 ... communication circuit, 275 ... recording medium control circuit, 277 ... recording medium, 279 ... flash memory control circuit, 281: Flash memory, 283: Switch detection circuit, 285 ... Various switches, 287 ... Buzzer, 291 ... Imaging unit, 293 ... Temporary storage unit, 294 ... Addition calculation unit 295 ... Image recording unit, 296 ... Image display unit, 297 ... Control unit, 298 ... Sound generation unit, 300 ... Communication contact, 301 ... Valve mode display, 302 ... Update time display, 311a ... notification information, 311b ... notification information, 311c ... notification information, 311d ... notification information, 311e ... notification information, 311f ... notification information, 3 11g ・ ・ ・ Notification information

Claims (5)

An imaging unit that repeatedly captures a subject image at a set cycle and outputs image data during bulb shooting,
Each time the image data is output, an addition operation unit that performs an addition operation with past image data and generates an added image;
An image display unit for displaying the added image;
In conjunction with the update of the image display in the image display unit,
An image pickup apparatus comprising:   The imaging apparatus according to claim 1, wherein the sound generation unit performs the predetermined sound generation when an image display update period in the image display unit is equal to or greater than a predetermined value.   The illumination unit that illuminates the image display unit, and the illumination unit illuminates the image display unit for a second predetermined time in conjunction with the update of the image display. The imaging device described in 1.   The imaging apparatus according to claim 1, wherein the image display unit displays notification information indicating that the bulb photographing is being performed.   During bulb shooting, the subject image is repeatedly taken at the set cycle, and the image data is output. Every time the image data is output, an addition operation with the past image data is performed to generate an added image. A method for controlling an image pickup apparatus, characterized by displaying the added image and generating a sound for a predetermined time in conjunction with the update of the image display.