JP4574916B2 - Electronic camera - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic camera that captures a subject image with an imaging device.
[0002]
[Prior art]
In order to obtain an appropriate exposure amount with the camera, an apex that performs an exposure calculation by the following equation (1) using the aperture value AV of the taking lens, the shutter time (exposure time) TV, the subject brightness BV, and the exposure sensitivity SV. Arithmetic is known.
[Expression 1]
EV = AV + TV = BV + SV (1)
However, EV is an exposure amount. In the case of a film camera, the SV is determined by the sensitivity of the film to be used, so the aperture value AV and shutter time TV are calculated according to the subject brightness BV. In the case of an electronic camera, when the exposure sensitivity SV of the imaging device can be changed, the aperture value AV, shutter time TV, and exposure sensitivity SV are calculated according to the subject brightness BV.
[0003]
[Problems to be solved by the invention]
In general, when an exposure sensitivity SV is increased in an electronic camera, noise superimposed on an image signal increases and image quality deteriorates. Therefore, in the exposure sensitivity change mode in which the exposure sensitivity SV can be changed, it is preferable to set an upper limit on the changed exposure sensitivity SV so that the S / N ratio of the image does not deteriorate below a predetermined value. On the other hand, there is a demand to prioritize a proper exposure over the S / N ratio of an image in a situation where exposure is likely to be underexposure, such as shooting in a dark place or high-speed shutter time TV. is there. Therefore, an electronic camera having a sensitization mode in which the exposure sensitivity SV is set higher than the above-described upper limit is known. In the exposure sensitivity change mode, an upper limit is set for the exposure sensitivity SV, and in the sensitization mode, the exposure sensitivity SV is set to be higher than the upper limit. End up.
[0004]
An object of the present invention is to provide an electronic camera in which an exposure calculation that can change an exposure sensitivity and an exposure calculation with a high exposure sensitivity do not compete with each other.
[0005]
[Means for Solving the Problems]
  An electronic camera according to the present invention includes an imaging device that captures a subject image through a photographing lens, a luminance detection device that detects subject luminance, an exposure sensitivity set in the imaging device, an exposure time set in the imaging device, and shooting. Exposure calculation circuit that performs exposure calculation using the aperture value set for the lens and subject brightness detected by the brightness detection device, and exposure sensitivity and exposure so that proper exposure can be obtained with the detected brightness value In accordance with the setting / cancellation of the first calculation mode for calculating the control exposure by automatically changing at least the exposure sensitivity among the plurality of exposure sensitivities included in the first range among the time and the aperture value. A first flag setting means for setting / resetting one flag, and an exposure sensitivity that is not included in the first range and is higher than any exposure sensitivity in the first range. In accordance with the setting / cancellation of the second calculation mode for calculating the control exposure by automatically changing at least one of the exposure time and the aperture value so that a proper exposure is obtained with the detected brightness value. A second flag setting means for setting / resetting the second flag, and maintaining the first calculation mode when an operation for setting the second calculation mode is performed in a state where the first flag is set; And an operation mode control means for maintaining the second operation mode when an operation for setting the first operation mode is performed in a state where the second flag is set.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a block diagram showing the configuration of the electronic camera according to the first embodiment of the present invention. In FIG. 1, an arithmetic circuit 101 is configured by a microcomputer or the like. The arithmetic circuit 101 inputs a signal output from each block to be described later, performs a predetermined calculation, and outputs a control signal to each block based on the calculation result.
The CCD 102 constitutes an image sensor. The CCD 102 captures an image of subject light that has passed through the photographing lens 103, and outputs an imaging signal to the imaging signal processing circuit 105. The CCD 102 is driven at a predetermined operation timing by a drive signal output from the drive circuit 104. Here, the CCD 102 is configured to be able to automatically change the imaging sensitivity (exposure sensitivity) in a predetermined step within a range corresponding to ISO 100 to ISO 1600 in an imaging sensitivity automatic change mode described later. In addition, the imaging sensitivity can be set to be equivalent to ISO 3200 in the sensitization mode described later.
[0007]
The imaging signal processing circuit 105 includes a correlated double sampling circuit that removes reset noise of the imaging signal, and an A / D conversion circuit that converts the analog imaging signal into a digital signal. The image data digitized by the imaging signal processing circuit 105 is output to the recording circuit 106. The recording circuit 106 sequentially inputs the image data signal-processed by the imaging signal processing circuit 105 and temporarily stores it. The recording medium 107 is configured by a flash memory or the like. The recording medium 107 is driven and controlled by a control signal output from the controller 108, and records image data temporarily stored in the recording circuit 106.
[0008]
The sensitivity setting operation member 109 outputs an operation signal to the arithmetic circuit 101 in accordance with the imaging sensitivity setting operation. The arithmetic circuit 101 sets the above-described imaging sensitivity of the CCD 102 according to the imaging sensitivity setting operation signal. The setting operation by the sensitivity setting operation member 109 can be manually changed in a predetermined step within a range corresponding to ISO 100 to ISO 3200. Specifically, ISO 100 equivalent, ISO 200 equivalent, ISO 400 equivalent, ISO 800 equivalent, ISO 1600 equivalent, ISO 3200 equivalent. In the present embodiment, the case where the imaging sensitivity is set to be equivalent to ISO 3200 is called a sensitization mode. The sensitization mode is set to a higher sensitivity than the range of imaging sensitivity that is normally set (equivalent to ISO 100 to ISO 1600). Effective for sports photography. However, it is a mode in which the S / N ratio is deteriorated and a rough image is likely to be obtained as compared with the imaging sensitivity (equivalent to ISO 100 to ISO 1600) that is normally set.
[0009]
The exposure mode setting operation member 110 includes a program auto exposure calculation mode (P), an aperture value priority auto exposure calculation mode (A), a shutter speed priority (exposure time priority) auto exposure calculation mode (S) according to the exposure mode setting operation. And an operation signal for switching to the manual exposure calculation mode (M) is output to the arithmetic circuit 101.
[0010]
The program auto exposure calculation mode is an exposure calculation mode in which the exposure time and the aperture value of the imaging apparatus 1 can be changed in a predetermined combination so that a proper exposure can be obtained and the control exposure is calculated. The aperture value priority auto exposure calculation mode is a calculation mode in which the exposure time can be changed and the control exposure is calculated so that an appropriate exposure can be obtained with a set aperture value. The exposure time priority auto exposure calculation mode is a calculation mode in which the aperture value can be changed and the control exposure is calculated so that a proper exposure can be obtained with the set exposure time. The manual exposure calculation mode is a calculation mode for calculating a deviation between the control exposure and the appropriate exposure according to the set exposure time and aperture value.
[0011]
The shutter speed setting operation member 111 outputs an operation signal to the arithmetic circuit 101 according to the shutter speed setting operation. The arithmetic circuit 101 sets a later-described shutter opening time according to the shutter speed setting operation signal, and controls the exposure time of the CCD 102 described above. Here, the shutter speed (exposure time) can be set in a predetermined step within a range of 1 second to 1/1000 second. The aperture setting operation member 112 outputs an operation signal to the arithmetic circuit 101 in accordance with the setting operation. The arithmetic circuit 101 sets an aperture value to be described later according to the aperture setting operation signal. The aperture value can be set in a predetermined step within a range of F2.8 to F22.
[0012]
The imaging sensitivity automatic change mode setting operation member 113 outputs an operation signal to the arithmetic circuit 101 according to the setting operation of the imaging sensitivity automatic change mode. The arithmetic circuit 101 sets and cancels the imaging sensitivity automatic change mode according to the input operation signal. In the imaging sensitivity automatic change mode, the control exposure is calculated by automatically changing the imaging sensitivity SV in accordance with the exposure deviation ΔEV so that a proper exposure can be obtained. The exposure deviation ΔEV is a difference between the control exposure and the appropriate exposure. When the imaging sensitivity automatic change mode is cancelled, the control exposure is calculated so that a proper exposure can be obtained with the set imaging sensitivity SV.
[0013]
The release switch 114 outputs a release operation signal to the arithmetic circuit 101 in conjunction with a release operation button (not shown). The display device 115 displays the presence / absence of imaging sensitivity automatic change mode setting, the presence / absence of sensitization mode setting, imaging sensitivity, and the like according to instructions from the arithmetic circuit 101. The photometric device 116 detects the subject brightness and outputs a detection signal to the arithmetic circuit 101. The motor drive circuit 117 controls the drive of the sequence motor 118 according to a command from the arithmetic circuit 101. The sequence motor 118 constitutes a sequence driving device (not shown), and performs up / down of a mirror (not shown), driving of a diaphragm (not shown), charging a shutter, and the like.
[0014]
The shutter control circuit 121 controls the holding and release of a front curtain and a rear curtain (not shown) of the shutter 122, respectively. The aperture position detection device 123 detects the aperture position corresponding to the aperture value and outputs a detection signal to the arithmetic circuit 101. The diaphragm locking device 124 locks the driving diaphragm and stops the diaphragm at a predetermined diaphragm value. The sequence switch 119 constitutes a sequence drive device (not shown) and generates a brake control timing for the sequence motor 118 and the like.
[0015]
The present invention prohibits simultaneous setting of the imaging sensitivity automatic change mode and the sensitization mode of the electronic camera. In particular, in the first embodiment, (1) when the electronic camera is set to the sensitization mode, the setting of the imaging sensitivity automatic change mode is prohibited, and (2) the electronic camera is set to the imaging sensitivity automatic change mode. In this case, the setting of the sensitization mode is prohibited.
[0016]
The imaging sensitivity changing process performed by the arithmetic circuit 101 of the electronic camera will be described with reference to the flowchart of FIG. The program according to the flowchart of FIG. 2 starts when a battery (not shown) is loaded in the electronic camera. In step S1 of FIG. 2, the arithmetic circuit 101 performs the following initial settings. The set sensitivity SV is set to 7 (equivalent to ISO400), the sensitization mode flag U is set to 0, the imaging sensitivity automatic change mode flag S is set to 0, and the process proceeds to step S2.
[0017]
Here, the apex value is used for SV. The range of setting sensitivity SV of the electronic camera according to the present embodiment is 5 ≦ SV ≦ 10, which corresponds to ISO100 to ISO3200. As described above, ISO 3200 equivalent is the sensitization mode. The sensitization mode flag U is set to 1 when the set sensitivity SV is set to be equivalent to ISO 3200 (set to the sensitization mode), and is set to 0 when the set sensitivity SV is set to be equivalent to ISO 100 to ISO 1600 (the sensitization mode is canceled). It is a flag to be set. The imaging sensitivity automatic change mode flag S is a flag that is set to 1 when the imaging sensitivity automatic change mode is set, and is set to 0 when the imaging sensitivity automatic change mode is canceled.
[0018]
In step S2, the arithmetic operation circuit 101 performs each setting process in accordance with the operation signal input from each setting operation member 109 to 113, and proceeds to step S3. Details of the setting process will be described later. In step S3, the arithmetic operation circuit 101 performs display processing for displaying the presence / absence of the imaging sensitivity automatic change mode setting, the presence / absence of the sensitization mode setting, and the set sensitivity SV on the display device 115, and proceeds to step S4. Details of the display process will be described later. In step S4, the arithmetic operation circuit 101 determines whether or not an imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S4 when S = 1 (set to the imaging sensitivity automatic change mode) and proceeds to step S6, and if S = 0 (cancels the imaging sensitivity automatic change mode), step S4 is executed. A negative determination is made and the process proceeds to step S5.
[0019]
In step S <b> 6, the arithmetic circuit 101 performs the imaging sensitivity automatic change mode process as follows.
(1) When the electronic camera is set to the programmed auto exposure calculation mode (P), it is set according to the exposure deviation ΔEV between the control exposure (AVc + TVc) calculated by the programmed auto exposure calculation and the appropriate exposure EV. The imaging sensitivity SV is automatically changed. However, AVc is a calculated control aperture value, and TVc is a calculated control shutter speed. The change range of the imaging sensitivity SV is 5 ≦ SV ≦ 9, which corresponds to ISO100 to ISO1600.
(2) When the electronic camera is set to the shutter speed priority auto exposure calculation mode (S), the exposure deviation ΔEV between the control exposure (AVc + TVs) calculated by the shutter speed priority auto exposure calculation and the appropriate exposure EV is set. Accordingly, the set imaging sensitivity SV is automatically changed. However, AVc is the calculated control aperture value, and TVs is the shutter speed set by the shutter speed setting operation member 111.
The change range of the imaging sensitivity SV is 5 ≦ SV ≦ 9, which corresponds to ISO100 to ISO1600.
(3) When the electronic camera is set to the aperture value priority auto exposure calculation mode (A), the exposure deviation ΔEV between the control exposure (AVs + TVc) calculated by the aperture value priority auto exposure calculation and the appropriate exposure EV is set. Accordingly, the set imaging sensitivity SV is automatically changed. However, AVs is an aperture value set by the aperture value setting operation member 112, and TVc is a calculated control shutter speed. The change range of the imaging sensitivity SV is 5 ≦ SV ≦ 9, which corresponds to ISO100 to ISO1600.
(4) When the electronic camera is set to the manual exposure calculation mode (M), the set imaging sensitivity is set according to the exposure deviation ΔEV between the control exposure (AVs + TVs) calculated by the manual exposure calculation and the appropriate exposure EV. SV is automatically changed. However, AVs is an aperture value set by the aperture value setting operation member 112, and TVs is a shutter speed set by the shutter speed setting operation member 111. The change range of the imaging sensitivity SV is 5 ≦ SV ≦ 9, which corresponds to ISO100 to ISO1600.
[0020]
The arithmetic circuit 101 returns to step S2 after performing the imaging sensitivity automatic change mode processing in step S6. Note that when the release operation signal is input from the release switch 114, the arithmetic circuit 101 performs a shooting sequence process (not shown). In step S5, the arithmetic circuit 101 determines whether or not the sensitization mode flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S5 when U = 1 (sensitization mode) and proceeds to step S7. If U = 0 (not in the sensitization mode), it makes a negative decision in step S5 and proceeds to step S8. move on.
[0021]
In step S7, the arithmetic operation circuit 101 performs sensitization mode processing and returns to step S2. When the sensitization mode is set, the control exposure is calculated by fixing the set imaging sensitivity SV to 10, that is, equivalent to ISO 3200, as compared with the above-described processing of the imaging sensitivity automatic change mode (step S6). Different.
[0022]
In step S8, the arithmetic operation circuit 101 performs the normal mode process (cancels both the imaging sensitivity automatic change mode and the sensitization mode) and returns to step S2. In the case of the normal mode, the control exposure is calculated without changing from the set imaging sensitivity SV as compared with the processing in the imaging sensitivity automatic change mode described above (step S6).
[0023]
Details of the setting process will be described with reference to the flowchart of FIG. In step S101 of FIG. 3, the arithmetic circuit 101 determines whether or not the setting of the imaging sensitivity automatic change mode has been changed. The arithmetic operation circuit 101 makes an affirmative decision in step S101 when an operation signal is input from the imaging sensitivity automatic change mode setting operation member 113 and proceeds to step S102. If an operation signal is not input, the operation circuit 101 makes a negative determination in step S101. The process proceeds to S106. In step S102, the arithmetic operation circuit 101 determines whether or not an imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S102 when S = 1 (set to the imaging sensitivity automatic change mode), and proceeds to step S103. If S = 0 (the imaging sensitivity automatic change mode is canceled), the arithmetic circuit 101 executes step S102. A negative determination is made and the process proceeds to step S104.
[0024]
In step S103, the arithmetic operation circuit 101 cancels the imaging sensitivity automatic change mode, sets 0 to the flag S, ends the processing in FIG. 3, and proceeds to step S3 in FIG. In step S104, the arithmetic operation circuit 101 determines whether or not the sensitization mode flag U = 0. The arithmetic operation circuit 101 makes an affirmative decision in step S104 when U = 0 (not in the sensitization mode) and proceeds to step S105, and makes a negative decision in step S104 when U = 1 (in the sensitization mode), as shown in FIG. The process ends, and the process proceeds to step S3 in FIG. Thereby, when the sensitization mode is set, the setting of the imaging sensitivity automatic change mode is prohibited. In step S105, the arithmetic operation circuit 101 sets the imaging sensitivity automatic change mode, sets 1 to the flag S, ends the processing in FIG. 3, and proceeds to step S3 in FIG.
[0025]
In step S106, which proceeds after making a negative determination in step S101 described above, the arithmetic operation circuit 101 determines whether or not the imaging sensitivity has been manually changed. The arithmetic operation circuit 101 makes an affirmative decision in step S106 when an operation signal is input from the sensitivity setting operation member 109, and proceeds to step S107. If an operation signal is not input, the operation circuit 101 makes a negative determination in step S106 and performs the processing of FIG. End and proceed to step S3 of FIG. In step S107, the arithmetic circuit 101 determines whether or not the sensitivity is increased. The arithmetic operation circuit 101 makes an affirmative decision in step S107 when the operation signal from the sensitivity setting operation member 109 instructs to increase the sensitivity, and proceeds to step S108. If the operation signal does not instruct an increase in sensitivity, the operation circuit 101 makes a negative determination in step S107. Then, the process proceeds to step S114.
[0026]
In step S108, the arithmetic circuit 101 determines whether or not the imaging sensitivity SV = 9. The arithmetic operation circuit 101 makes an affirmative decision in step S108 when SV = 9 (equivalent to ISO 1600) and proceeds to step S109. If SV ≠ 9, the operation circuit 101 makes a negative decision in step S108 and proceeds to step S112. In step S109, the arithmetic operation circuit 101 determines whether or not the imaging sensitivity automatic change mode flag S = 0. The arithmetic operation circuit 101 makes an affirmative decision in step S109 when S = 0 (the imaging sensitivity automatic change mode is canceled), and proceeds to step S110. When S = 1 (sets in the imaging sensitivity automatic change mode), the arithmetic circuit 101 executes step S109. A negative determination is made, the processing in FIG. 3 is terminated, and the process proceeds to step S3 in FIG. Thereby, the setting of the sensitization mode is prohibited when the imaging sensitivity automatic change mode is set.
[0027]
In step S110, the arithmetic circuit 101 sets 10 (equivalent to ISO 3200) to the imaging sensitivity SV, and then proceeds to step S111. Thereby, the sensitization mode is set. In step S111, the arithmetic operation circuit 101 sets 1 to the sensitization mode flag U, ends the processing of FIG. 3, and proceeds to step S3 of FIG.
[0028]
In step S112, the arithmetic operation circuit 101 determines whether or not the sensitization mode flag U = 0. The arithmetic operation circuit 101 makes an affirmative decision in step S112 when U = 0 (not in the sensitization mode), and proceeds to step S113. If U = 1 (sensitization mode), the operation circuit 101 makes a negative decision in step S112 according to FIG. The process ends, and the process proceeds to step S3 in FIG. Thereby, the sensitivity is not further increased when the sensitization mode is set. In step S113, the arithmetic operation circuit 101 adds 1 to the imaging sensitivity SV, ends the processing in FIG. 3, and proceeds to step S3 in FIG. Thereby, the set imaging sensitivity is increased by one step.
[0029]
In step S114, the arithmetic operation circuit 101 makes a determination as to whether or not the sensitivity has been reduced. The arithmetic operation circuit 101 makes an affirmative decision in step S114 when the operation signal from the sensitivity setting operation member 109 instructs to decrease the sensitivity, and proceeds to step S115. The arithmetic operation circuit 101 makes a negative determination in step S114 when the operation signal does not instruct a decrease in sensitivity, ends the processing in FIG. 3, and proceeds to step S3 in FIG.
[0030]
In step S115, the arithmetic circuit 101 determines whether or not the sensitization flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S115 when U = 1 (sensitization mode) and proceeds to step S116. If U = 0 (not in the sensitization mode), it makes a negative decision in step S115 and proceeds to step S118. move on. In step S116, the arithmetic operation circuit 101 sets 9 (equivalent to ISO 1600) for the imaging sensitivity SV, and then proceeds to step S117. Thereby, the sensitization mode is canceled. In step S117, the arithmetic operation circuit 101 sets 0 in the flag U, ends the processing in FIG. 3, and proceeds to step S3 in FIG.
[0031]
In step S118, the arithmetic operation circuit 101 determines whether or not the imaging sensitivity SV = 5 (equivalent to ISO 100). The arithmetic operation circuit 101 makes an affirmative decision in step S118 when SV = 5, ends the process of FIG. 3, and proceeds to step S3 of FIG. In this case, since the sensitivity setting range is the lower limit, the setting process is terminated without reducing the sensitivity.
On the other hand, when SVs ≠ 5, the arithmetic operation circuit 101 makes a negative determination in step S118 and proceeds to step S119. In step S119, the arithmetic operation circuit 101 subtracts 1 from the imaging sensitivity SV, ends the processing in FIG. 3, and proceeds to step S3 in FIG. Thereby, the set imaging sensitivity is lowered by one step.
[0032]
Details of the display processing will be described with reference to the flowchart of FIG. In step S201 of FIG. 4, the arithmetic circuit 101 determines whether or not the imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S201 when S = 1 (set to the imaging sensitivity automatic change mode), and proceeds to step S203. If S = 0 (the imaging sensitivity automatic change mode is canceled), the arithmetic circuit 101 proceeds to step S201. A negative determination is made and the process proceeds to step S202.
[0033]
In step S203, the arithmetic operation circuit 101 displays a character or mark indicating that the imaging sensitivity automatic change mode is set on the display device 115, ends the processing of FIG. 4, and proceeds to step S4 of FIG. In the case of characters, for example, “ISO Auto” is displayed.
[0034]
In step S202, the arithmetic circuit 202 determines whether or not the sensitization mode flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S202 when U = 1 (sensitization mode) and proceeds to step S204. If U = 0 (not in the sensitization mode), it makes a negative decision in step S202 and proceeds to step S205. move on. In step S204, the arithmetic operation circuit 101 displays a character or mark indicating that the sensitization mode is set on the display device 115, ends the processing in FIG. 4, and proceeds to step S3 in FIG. In the case of characters, for example, “ISO HI” is displayed.
[0035]
In step S205, the arithmetic operation circuit 101 causes a character corresponding to the set imaging sensitivity SV to be lit on the display device 115, ends the processing in FIG. 4, and proceeds to step S3 in FIG. For example, since SV = 7 corresponds to ISO400, “ISO 400” is displayed.
[0036]
As described above, according to the first embodiment, when the electronic camera is set to the sensitization mode, the setting of the imaging sensitivity automatic change mode is prohibited, and the electronic camera is set to the imaging sensitivity automatic change mode. Since the setting of the sensitization mode is prohibited, the operation of changing the imaging sensitivity within the range equivalent to ISO 100 to ISO 1600 by the processing of the imaging sensitivity automatic change mode (step S6), and the sensitization mode In this process (step S7), the operation performed by setting the imaging sensitivity to be equivalent to ISO 3200 is performed alternatively, and it is possible to prevent the operations from competing with each other. Furthermore, unless the setting change operation is performed by the photographer, the image pickup ratio is not changed from the imaging sensitivity automatic change mode to the sensitization mode and the sensitization mode to the imaging sensitivity automatic change mode. Is prevented from changing.
[0037]
(Second embodiment)
In the second embodiment, when the electronic camera is set to the imaging sensitivity automatic change mode, the imaging sensitivity automatic change mode is canceled when the electronic camera is set to the sensitization mode. The flowchart in FIG. 5 explains the setting process according to the second embodiment, and is used instead of the flowchart in FIG. 3 described above. In FIG. 5, the same processes as those in FIG. 3 are denoted by the same step numbers as those in FIG. 5 is different from FIG. 3 in that step S109 is omitted and step S121 and step S122 are added.
[0038]
By omitting step S109, the arithmetic operation circuit 101 sets the imaging sensitivity SV to 10 (equivalent to ISO 3200) regardless of the setting / cancellation of the imaging sensitivity automatic change mode in step S110, and proceeds to step S111. Thereby, the sensitization mode is set. In step S111, the arithmetic circuit 101 sets 1 in the flag U, and proceeds to step S121.
[0039]
In step S121, the arithmetic circuit 101 determines whether or not the imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S121 when S = 1 (set to the imaging sensitivity automatic change mode) and proceeds to step S122, and if S = 0 (cancels the imaging sensitivity automatic change mode), the arithmetic circuit 101 executes step S121. A negative determination is made, the processing in FIG. 5 is terminated, and the process proceeds to step S3 in FIG. In step S122, the arithmetic operation circuit 101 cancels the imaging sensitivity automatic change mode, sets 0 to the flag S, ends the processing in FIG. 5, and proceeds to step S3 in FIG.
[0040]
As described above, according to the second embodiment, when the electronic camera is set to the imaging sensitivity automatic change mode, the imaging sensitivity automatic change mode is canceled when the electronic camera is set to the sensitization mode. Then, the imaging sensitivity is set to be equivalent to ISO 3200 in the operation of changing the imaging sensitivity within the range equivalent to ISO 100 to ISO 1600 by the processing of the imaging sensitivity automatic change mode (step S6) and the processing of the sensitization mode (step S7). The operation to be performed is performed alternatively, and it is possible to prevent the operations from competing with each other.
[0041]
(Third embodiment)
In the third embodiment, when the electronic camera is set to the sensitization mode, the sensitization mode is canceled when the imaging sensitivity automatic change mode is set.
The flowchart in FIG. 6 describes the setting process according to the third embodiment, and is used instead of the flowchart in FIG. 3 described above. In FIG. 6, the same processes as those in FIG. 3 are denoted by the same step numbers as those in FIG. 6 is different from FIG. 3 in that step S104 and step S105 are omitted and steps S131 to S134 are added.
[0042]
By omitting step S104, the arithmetic operation circuit 101 sets the imaging sensitivity automatic change mode in step S131 regardless of the setting / cancellation of the sensitization mode, sets 1 to the flag S, and proceeds to step S132. . In step S132, the arithmetic operation circuit 101 determines whether or not the sensitization mode flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S132 when U = 1 (sensitization mode) and proceeds to step S133, and makes a negative decision in step S132 when U = 0 (not in the sensitization mode), as shown in FIG. The process ends, and the process proceeds to step S3 in FIG.
[0043]
In step S133, the arithmetic operation circuit 101 sets 0 for the flag U before proceeding to step S134. In step S134, the arithmetic operation circuit 101 sets 9 (equivalent to ISO 1600) for the imaging sensitivity SV, ends the processing in FIG. 6, and proceeds to step S3 in FIG. Thereby, the sensitization mode is canceled.
[0044]
As described above, according to the third embodiment, when the electronic camera is set to the sensitizing mode, the sensitizing mode is canceled when the imaging sensitivity automatic change mode is set. An operation for changing the imaging sensitivity within a range corresponding to ISO 100 to ISO 1600 by the processing in the automatic sensitivity change mode (step S6) and an operation performed by setting the imaging sensitivity to be equivalent to ISO 3200 in the processing in the sensitization mode (step S7) Is performed alternatively, and it is possible to prevent the operations of each other from competing with each other.
[0045]
(Fourth embodiment)
In the fourth embodiment, the setting operation / cancellation operation of the imaging sensitivity automatic setting mode is performed by the sensitivity setting operation member. In this case, the imaging sensitivity automatic change mode setting operation member 113 and the sensitivity setting operation member 109 in FIG. 1 are omitted, and a sensitivity setting operation member 109A (not shown) is newly added. The sensitivity setting operation member 109A is configured by, for example, a dial switch, and outputs an operation signal to the arithmetic circuit 101 in accordance with the imaging sensitivity setting operation. The arithmetic circuit 101 sets the above-described imaging sensitivity of the CCD 102 according to the imaging sensitivity setting operation signal.
[0046]
The setting operation by the sensitivity setting operation member 109A can be manually changed in a predetermined step within a range corresponding to ISO 100 to ISO 3200. Furthermore, it is possible to set / cancel the imaging sensitivity automatic setting mode. Specifically, in accordance with the clockwise rotation operation, the setting is cyclic as follows: ISO 100 equivalent → ISO 200 equivalent → ISO 400 equivalent → ISO 800 equivalent → ISO 1600 equivalent → ISO 3200 equivalent → ISO auto → ISO 100 equivalent. In the case of a counterclockwise rotation operation, the reverse of the above is set.
[0047]
In the case of setting to ISO3200 equivalent, it is a sensitization mode. ISO auto corresponds to an imaging sensitivity automatic setting mode. That is, in ISO auto, the imaging sensitivity automatic setting mode is set, and in settings other than ISO auto, the imaging sensitivity automatic setting mode is canceled. Note that the normal mode is selected when neither ISO auto nor ISO 3200 is equivalent. As described above, in the fourth embodiment, the sensitizing mode, the ISO auto, and the normal mode are alternatively set.
[0048]
The flowchart in FIG. 7 explains the setting process according to the fourth embodiment, and is used instead of the flowchart in FIG. 3 described above. In step S301 in FIG. 7, the arithmetic circuit 101 determines whether or not the imaging sensitivity has been manually changed. The arithmetic operation circuit 101 makes an affirmative decision in step S301 when an operation signal is input from the sensitivity setting operation member 109A, and proceeds to step S302. If an operation signal is not input, the operation circuit 101 makes a negative determination in step S301 and performs the processing of FIG. End and proceed to step S3 of FIG. In step S302, the arithmetic operation circuit 101 determines whether or not the sensitivity is increased. The arithmetic operation circuit 101 makes an affirmative decision in step S302 when the operation signal from the sensitivity setting operation member 109A instructs to increase the sensitivity, and proceeds to step S303. If the operation signal does not instruct an increase in sensitivity, the operation circuit 101 makes a negative determination in step S302. Then, the process proceeds to step S313.
[0049]
In step S303, the arithmetic circuit 101 determines whether or not the imaging sensitivity SV = 9 (equivalent to ISO 1600). The arithmetic operation circuit 101 makes an affirmative decision in step S303 when SV = 9 and proceeds to step S304. If SV ≠ 9, the operation circuit 101 makes a negative decision in step S303 and proceeds to step S306. In step S304, the arithmetic operation circuit 101 sets 10 (equivalent to ISO 3200) for the imaging sensitivity SV, and then proceeds to step S305. Thereby, the sensitization mode is set. In step S305, the arithmetic operation circuit 101 sets 1 in the flag U, ends the processing in FIG. 7, and proceeds to step S3 in FIG.
[0050]
In step S306, the arithmetic operation circuit 101 makes a decision as to whether or not the sensitization mode flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S306 when U = 1 (sensitization mode) and proceeds to step S307. If U = 0 (not in the sensitization mode), it makes a negative decision in step S306 and proceeds to step S309. move on. In step S307, the arithmetic operation circuit 101 sets the imaging sensitivity automatic change mode (ISO auto), sets 1 to the flag S, and proceeds to step S308. In step S308, the arithmetic operation circuit 101 sets 5 (equivalent to ISO 100) to the imaging sensitivity SV to cancel the sensitization mode, and proceeds to step S330. In step S330, the arithmetic operation circuit 101 sets 0 in the flag U, ends the processing in FIG. 7, and proceeds to step S3 in FIG. As a result, the sensitization mode is canceled, and the exposure calculation is performed with the imaging sensitivity equivalent to ISO 100 during the exposure calculation in the imaging sensitivity automatic change mode, and the set imaging sensitivity SV is set according to the exposure deviation ΔEV with respect to the appropriate exposure EV. It will be changed automatically.
[0051]
In step S309, the arithmetic operation circuit 101 makes a decision as to whether or not the imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S309 when S = 1 (set to the imaging sensitivity automatic change mode), and proceeds to step S310. If S = 0 (releases the imaging sensitivity automatic change mode), the arithmetic circuit 101 proceeds to step S309. A negative determination is made and processing proceeds to step S312. In step S310, the arithmetic operation circuit 101 sets 5 (equivalent to ISO 100) for the imaging sensitivity SV, and proceeds to step S311.
In step S311, the arithmetic operation circuit 101 cancels the imaging sensitivity automatic change mode, sets 0 to the flag S, ends the processing in FIG. 7, and proceeds to step S3 in FIG. In step S312, the arithmetic circuit 101 adds 1 to the imaging sensitivity SV, ends the processing in FIG. 7, and proceeds to step S3 in FIG. Thereby, the set imaging sensitivity is increased by one step.
[0052]
In step S313, in which the negative determination is made in step S302 described above, the arithmetic operation circuit 101 determines whether or not the sensitivity is lowered. The arithmetic operation circuit 101 makes an affirmative decision in step S313 when the operation signal from the sensitivity setting operation member 109A instructs to lower the sensitivity and proceeds to step S314. If the operation signal does not instruct a lowering of sensitivity, the operation circuit 101 makes a negative determination in step S313. 7 is terminated and the process proceeds to step S3 in FIG.
[0053]
In step S314, the arithmetic operation circuit 101 determines whether or not the imaging sensitivity automatic change mode flag S = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S314 when S = 1 (set to the imaging sensitivity automatic change mode), and proceeds to step S315. If S = 0 (the imaging sensitivity automatic change mode is canceled), the arithmetic circuit 101 executes step S314. A negative determination is made and processing proceeds to step S318. In step S315, the arithmetic operation circuit 101 sets 10 (equivalent to ISO 3200) for the imaging sensitivity SV, and proceeds to step S316. Thereby, the sensitization mode is set. In step S316, the arithmetic operation circuit 101 sets 1 for the flag U before proceeding to step S317. In step S317, the arithmetic operation circuit 101 cancels the imaging sensitivity automatic change mode, sets 0 to the flag S, ends the processing in FIG. 7, and proceeds to step S3 in FIG.
[0054]
In step S318, the arithmetic operation circuit 101 determines whether or not the imaging sensitivity SV = 5 (equivalent to ISO 100). The arithmetic operation circuit 101 makes an affirmative decision in step S318 when SV = 5 and proceeds to step S319. If SV ≠ 5, the operation circuit 101 makes a negative decision in step S318 and proceeds to step S320. In step S319, the arithmetic operation circuit 101 sets the imaging sensitivity automatic change mode (ISO auto), sets 1 to the flag S, ends the processing in FIG. 7, and proceeds to step S3 in FIG. As a result, during the exposure calculation in the imaging sensitivity automatic change mode, the exposure calculation is performed with the imaging sensitivity equivalent to ISO 100, and the set imaging sensitivity SV is automatically changed according to the exposure deviation ΔEV with respect to the appropriate exposure EV. become.
[0055]
In step S320, the arithmetic operation circuit 101 makes a decision as to whether or not the sensitization mode flag U = 1. The arithmetic operation circuit 101 makes an affirmative decision in step S320 when U = 1 (sensitization mode) and proceeds to step S321. If U = 0 (not in the sensitization mode), it makes a negative decision in step S320 and proceeds to step S323. move on. In step S321, the arithmetic operation circuit 101 sets 9 (equivalent to ISO 1600) for the imaging sensitivity SV, and then the operation proceeds to step S322. Thereby, the sensitization mode is canceled. In step S322, the arithmetic operation circuit 101 sets 0 for the flag U, ends the processing of FIG. 3, and proceeds to step S3 of FIG. In step S323, the arithmetic operation circuit 101 subtracts 1 from the imaging sensitivity SV, ends the processing of FIG. 7, and proceeds to step S3 of FIG. Thereby, the set imaging sensitivity is lowered by one step.
[0056]
As described above, in the fourth embodiment, the setting / canceling operation of the imaging sensitivity automatic setting mode is performed by the sensitivity setting operation member 109A, and the sensitivity setting operation member 109A is configured by a dial switch to automatically capture the imaging sensitivity. The setting mode (ISO auto), the sensitization mode (equivalent to ISO 3200) and the normal mode (equivalent to ISO 100 to ISO 1600) are alternatively switched. Accordingly, the imaging sensitivity is set to be equivalent to ISO 3200 by the operation of changing the imaging sensitivity within the range equivalent to ISO 100 to ISO 1600 by the processing of the imaging sensitivity automatic change mode (step S6) and the processing of the sensitization mode (step S7). Thus, it is possible to prevent contention with the operation performed.
[0058]
【The invention's effect】
  The electronic camera according to the present invention can prevent a plurality of exposure calculation operations from competing.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an electronic camera according to a first embodiment.
FIG. 2 is a flowchart illustrating a flow of imaging sensitivity change processing performed by an arithmetic circuit.
FIG. 3 is a flowchart illustrating a flow of setting processing performed in an arithmetic circuit.
FIG. 4 is a flowchart illustrating a flow of display processing performed in an arithmetic circuit.
FIG. 5 is a flowchart illustrating a flow of setting processing according to the second embodiment.
FIG. 6 is a flowchart illustrating a flow of setting processing according to the third embodiment.
FIG. 7 is a flowchart illustrating a flow of setting processing according to a fourth embodiment.
[Explanation of symbols]
101 ... arithmetic circuit, 102 ... CCD,
109 ... Sensitivity setting operation member, 110 ... Exposure mode setting operation member,
111 ... Shutter speed setting operation member, 112 ... Aperture setting operation member,
113 ... Imaging sensitivity automatic change mode setting operation member,
115: Display device, 116: Photometric device

Claims (2)

An imaging device for imaging a subject image through a taking lens;
A luminance detection device for detecting subject luminance;
Exposure calculation using exposure sensitivity set in the imaging device, exposure time set in the imaging device, aperture value set in the photographing lens, and subject brightness detected by the brightness detection device An exposure calculation circuit for performing
Among the plurality of exposure sensitivities included in the first range, at least the exposure sensitivity among the exposure sensitivity, the exposure time, and the aperture value is automatically selected so that a proper exposure is obtained with the detected luminance value. a first flag setting means for the first flag is set / reset according to the setting / release of the first operational mode for calculating the specific changes to control exposure,
An exposure sensitivity that is not included in the first range and that is higher than any exposure sensitivity in the first range is set so that a proper exposure can be obtained with the detected luminance value. In addition, second flag setting means for setting / resetting the second flag in accordance with setting / cancellation of the second calculation mode for calculating the control exposure by automatically changing at least one of the exposure time and the aperture value When,
The first calculation mode is maintained when an operation for setting the second calculation mode is performed in a state where the first flag is set, and the second flag is set Calculation mode control means for maintaining the second calculation mode when an operation for setting the first calculation mode is performed in
An electronic camera comprising: The electronic camera according to claim 1,
  The electronic camera is characterized in that the operation for setting the second calculation mode is operated by the exposure sensitivity setting operation member.

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