JP2018189674A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that it is difficult for a photographer to recognize a position in a program diagram, when a lens device difficult for the photographer to recognize a full-aperture value beforehand is mounted.SOLUTION: An imaging apparatus is provided that comprises: imaging means which images a subject; an optical device which is mountable to and demountable from the imaging means and comprises a diaphragm mechanism; automatic exposure means which automatically adjusts exposures on the basis of an arbitrary program diagram with respect to the imaged subject; diagram position information calculation means which calculates position where a current exposure setting value set by the automatic exposure means is present in the program diagram; full-aperture value detection means detecting a full-aperture value of the diaphragm mechanism from the optical device; and display means displaying diagram position information calculated by the diagram position information calculation means. The diagram position information display means performs a diagram position display which is indicative of a reliable value when the full-aperture value can be detected by the full-aperture value detection means, and the diagram position information display means performs a diagram position display which is indicative of a non-reliable value when the full-aperture value cannot be obtained by the full-aperture value detection means.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an imaging apparatus capable of displaying an automatic exposure interlocking range.

  Conventionally, as an automatic exposure control (AE) mode of an imaging apparatus, there are an Av mode that prioritizes an aperture, a Tv mode that prioritizes a shutter, an AGC mode that prioritizes a shutter and an aperture, and the like. In the Av mode, the photographer sets an aperture value, and the imaging device performs shooting by changing the shutter and gain. In the Tv mode, the photographer sets the shutter, and the image pickup apparatus changes the aperture and gain for shooting. In the AGC mode, the photographer sets an aperture and a shutter, and the imaging apparatus performs shooting by changing the gain.

  Patent Document 1 proposes an imaging apparatus that displays a combination of a shutter speed and an aperture value corresponding to a change in ambient brightness as a program diagram in an automatic exposure program. However, depending on the ambient light, it may be near the end of the program diagram, and automatic control using other exposure parameters may not be able to follow the change of the ambient light (cannot achieve proper exposure).

  Therefore, Patent Document 2 proposes an example in which a combination range and a position thereof are displayed in association with each other for each combination of exposure parameters in the automatic exposure program. In other words, by displaying the position on the program diagram and the margin to the end of the program diagram, it is possible to provide a guide to the photographer as to whether or not shooting is possible with appropriate exposure when the ambient light changes. it can.

JP 62-201427 A JP 2011-59499 A

  However, among various lens devices that can be attached to and detached from the imaging device, it is difficult to previously grasp the open end position of the aperture value. When such a lens apparatus is attached to the imaging apparatus, it is difficult to accurately grasp the position on the program diagram. Furthermore, the open aperture value may change due to the operation of an extender or zoom lens provided in the lens apparatus, making it difficult to grasp the open end position.

In order to solve the above problems, an imaging apparatus according to the present invention provides:
An image capturing unit for capturing an image of an object, an optical device that is detachable from the image capturing unit and includes an aperture mechanism, and an object captured by the image capturing unit are automatically exposed based on an arbitrary program diagram. An imaging apparatus comprising: automatic exposure means for adjusting; and diagram position information calculation means for calculating where in the program diagram the current exposure setting value set by the automatic exposure means is located An open aperture value detecting means for detecting an open aperture value of the aperture mechanism from the optical device, a display means for displaying the diagram position information calculated by the diagram position information calculating means, If the open aperture value can be detected by the open aperture value detection means, the diagram position information display means displays a diagram position indicating a reliable value, and the open aperture value is displayed. The value detecting means, when the open aperture value is not obtained, depending the diagram positional information display means, and performs the diagram position display indicating a unreliable value.

  According to the imaging device of the present invention, the position on the program diagram at the current exposure setting value is switched by switching the current position display on the program diagram according to the reliability of the aperture value acquired from the lens device. Can be grasped.

External view of digital video camera Block diagram showing the internal configuration of a digital video camera Example of program diagram in Tv mode Flowchart executed by the camera control unit 119 and the image processing unit 118 Subroutine of S1030 Example of program diagram in Av mode Example of program diagram in AGC mode Subroutine of S1080 Subroutine of S1086 Subroutine of S1090 Example of screen display by characters at program diagram position Example of screen display with program diagram position indicator

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows the appearance of a lens-interchangeable digital video camera (hereinafter simply referred to as camera 100) as an image pickup apparatus that is Embodiment 1 of the present invention. In this embodiment, an interchangeable lens type digital video camera will be described. However, processing described later can be performed in various interchangeable lens imaging apparatuses such as a single-lens reflex camera and a mirrorless single-lens camera.

  In FIG. 1, a monitor 28 and an electronic viewfinder 29 display images and various types of information. The START / STOP button 61 is an operation member that is operated by a user (photographer) instructing the start and end of imaging (recording). The power / mode switch 72 is an operation member that is operated by the user in order to switch the power on / off, the imaging mode, and the reproduction mode. On the operation panel 70, a plurality of operation members such as various switches and buttons for accepting operations by the user are arranged. The connector 12 is a connector for outputting a video signal from the camera 100 to an external monitor or an external recording device, and constitutes an external output I / F unit 120. The battery cover 11 is a cover that holds a battery loaded in the camera 100. The access lamp 13 is a lamp that displays the state of the recording card slot.

  FIG. 2 shows the internal configuration of the camera 100. In FIG. 2, each function is separately shown as a component, but these may be realized by hardware such as one or a plurality of ASICs or a programmable logic array (PLA). Moreover, it may be implement | achieved when programmable processors, such as CPU and MPU, execute software.

  The camera 100 has a display unit 107 including the monitor 28, the electronic viewfinder 29, and the access lamp 13 shown in FIG. The external output unit 121 is exposed on the outer surface of the camera 100 and is connected to the external output I / F unit 120.

  The interchangeable lens 101 houses a photographing optical system (not shown) including a focus lens, a zoom lens, a diaphragm, a vibration-proof shift lens, an extender, and the like. The ND filter 103 is provided in the camera 100 in order to adjust (reduce) the amount of incident light separately from the diaphragm provided in the interchangeable lens 101.

  The imaging element 102 has a configuration in which a plurality of pixels each including a photoelectric conversion element are two-dimensionally arranged. The image sensor 102 photoelectrically converts a subject image (optical image) formed by the photographing optical system for each pixel, that is, captures an image to generate an analog signal, which is converted into a digital signal by an A / D conversion circuit. RAW image data in pixel units is output.

  The memory I / F unit 116 writes RAW image data for all pixels output from the image sensor 102 to the memory 117, reads out the RAW image data held in the memory 117, and outputs the RAW image data to the image processing unit 118. . The memory 117 is a volatile storage medium that stores all-pixel RAW image data for several frames.

  The image processing unit 118 performs processing such as gamma correction, color separation, and color difference matrix on the RAW image data for all pixels from the memory I / F unit 116, and adds a synchronization signal to record or display video. Output as data. Further, the image processing unit 118 obtains a photometric value from the luminance value of each pixel of the RAW image data input to the image processing unit 118 and provides it to the camera control unit 119 described later.

  The camera control unit 119 includes a CPU, a ROM, a RAM, and the like. The CPU controls the overall operation of the camera 100 by developing and executing a computer program stored in the ROM in a work area of the RAM. In addition, the camera control unit 119 executes processing described later by executing a computer program stored in the ROM. The RAM holds constants and variables for the operation of the camera control unit 119, and develops a program read from the ROM. Evaluation value calculation processing and exposure control processing, which will be described later, are executed by the camera control unit 119.

  The recording medium I / F unit 104 is an interface between the recording medium 105 and the camera 100 and controls recording of video data input from the image processing unit 118 to the recording medium 105 and reading of recorded video data. The recording medium 105 is composed of a semiconductor memory or the like.

  The display I / F unit 106 performs a superimposing process and a resizing process on the video data from the image processing unit 118 and the image data drawn by the GPU 115 and held in the VRAM (Video RAM). Video or image data is output to the display unit 107. The display unit 107 displays the video data output from the display I / F unit 106 for angle of view confirmation. The GPU 115 is a rendering engine that draws various information displays and menu screens of the video camera in the VRAM.

  The gain control unit 109, the shutter control unit 110, the ND control unit 111, and the aperture control unit 112 are provided for exposure control. The camera control unit 119 controls each of the control units 109 to 112 based on the above-described photometric value provided from the image processing unit 118 or an operation parameter manually set by the user. The gain control unit 109 controls the gain of the image sensor 102. The shutter control unit 110 controls the shutter speed of the image sensor 102. The ND control unit 111 controls the amount of light incident on the image sensor 102 via the ND filter 103. The aperture control unit 112 controls the aperture mechanism of the interchangeable lens 101. The aperture control unit 112 acquires the current aperture value and the full aperture value from the interchangeable lens 101.

  The camera control unit 119 has an evaluation value calculation function and an exposure control function. An evaluation value for determining whether or not the photographed image is in an appropriate exposure state is calculated from the photometric value output from the image processing unit 118 described above. In response to the calculation result of the evaluation value, a control command is issued to the gain control unit 109, the shutter control unit 110, the ND control unit 111, and the aperture control unit 112. The process is repeatedly executed until an appropriate luminance level of the subject image is obtained based on a preset program diagram. For example, FIG. 3 shows a program diagram when the Tv mode is selected.

  The camera control unit 119 performs AF control via the focus control unit 113 when the user selects the AF (autofocus) mode through the operation of the AF / MF switch 135 provided on the interchangeable lens 101. Specifically, the focus detection unit 108 generates a contrast evaluation value signal from the high frequency component of the video data output from the image sensor 102. The camera control unit 119 controls driving of the focus lens so as to search for an in-focus position where the contrast evaluation value signal reaches a peak. On the other hand, when the MF (manual focus) mode is selected through the operation of the AF / MF switch 135, the camera control unit 119 stops the AF control. Thereby, the position of the focus lens can be adjusted according to the rotation operation of the focus ring 134 provided on the interchangeable lens 101 by the user.

  The camera control unit 119 performs zoom control via the zoom control unit 136 when the user selects the Servo mode through the operation of the Servo / Mual switch 139 provided on the interchangeable lens 101. Specifically, a signal operated by a zoom operation member (not shown) provided in the external operation unit 123 described later is input to the camera control unit 119 through the external operation I / F unit 122. The camera control unit 119 performs speed control or position control via the zoom control unit 136 based on the input operation amount of the zoom operation member. The camera control unit 119 can acquire position information and focal length information of the zoom lens of the interchangeable lens 101 through the zoom control unit 136. On the other hand, when the Manual mode is selected through the operation of the Servo / Manual switch 139, the camera control unit 119 or the interchangeable lens 101 stops zoom control. Thereby, the position of the zoom lens can be adjusted according to the rotation operation of the zoom ring 138 provided on the interchangeable lens 101 by the user.

  The EXT change switch 140 provided in the interchangeable lens 101 is used for switching an extender provided in the interchangeable lens 101. The camera control unit 119 can acquire the magnification information of the extender of the interchangeable lens 101 through the EXT state acquisition unit 137. At this time, focal length information when the extender is valid can be obtained from the interchangeable lens 101. It is known that when the focal length is increased, the amount of light incident on the image sensor decreases when an aperture stop value exceeding the effective aperture is required. At this time, a phenomenon called “F drop” occurs, and the position that is narrower than the original may be the full aperture position.

  The camera control unit 119 detects a motion vector as information (shake information) indicating shake that occurs during imaging from the video data (continuous frame images) from the image processing unit 118. Then, based on the detected motion vector, the camera control unit 119 uses an image stabilization shift lens in the interchangeable lens 101 through the optical image stabilization control unit 114 and is orthogonal to the optical axis so as to reduce (correct) image blur. An optical image stabilization process for shifting (shifting) in the direction to be performed is performed.

  The external output I / F unit 120 obtained by performing resizing processing on the video data from the image processing unit 118 and applying signal conversion and control signals suitable for the standard of the external output unit 121. Video data is output to the external output unit 121. The external output unit 121 is a terminal for externally outputting video data, and is an SDI terminal, an HDMI (registered trademark) terminal, or the like. A monitor display or an external recording device can be connected to the external output I / F unit 120.

  The external operation I / F unit 122 is an interface that receives a control instruction from the external operation unit 123 and notifies the camera control unit 119, and receives remote control such as an infrared light receiving unit, a wireless LAN interface, and a LANC (registered trademark) terminal. It corresponds to the part. The external operation unit 123 corresponds to a remote control transmission unit that transmits various instructions to the external operation I / F unit 122.

  Next, exposure control processing performed by the camera control unit 119 in the camera 100 will be described with reference to the flowchart of FIG.

  When the camera 100 is turned on, a computer program is loaded into the camera control unit 119 as described above, and processing is executed in order from S1010 in FIG. Note that when the processing from S1100 in FIG. 4 is executed, the loop processing is again performed from S1020. However, the processing from S1020 to S1100 will be described for each frame.

  In S1010 of FIG. 4, the initialization process of the camera control unit 119 when the camera 100 is turned on is executed. For example, the gain is set to 0 dB for the gain control unit 109. For the shutter control unit 110, the shutter speed is set to 1/60 seconds. For the ND control unit 111, an ND filter having the maximum transmittance is set. An open aperture value is set for the aperture control unit 112. Each control part 109-112 controls according to the set value.

  Next, in S1020 of FIG. 4, the exposure mode is set. The user operates the external operation unit 123 shown in FIG. 2 to select one of the exposure modes among the Tv mode, Av mode, and AGC mode. The selected exposure mode is notified to the camera control unit 119 via the external operation I / F unit 122 and set as the exposure mode.

  In S1030 of FIG. 4, the program diagram is switched. The subroutine of S1030 is shown in FIG.

  In S1031 of FIG. 5, the exposure mode selected in S1020 described above is determined. If it is the Tv mode, the process proceeds to S1032, if it is the Av mode, the process proceeds to S1033, and if it is the AGC mode, the process proceeds to S1034. In S1032, a Tv program diagram is set. The Tv program diagram is as shown in FIG. In S1033, an Av program diagram is set. An example of an Av program diagram is shown in FIG. In S1034, an AGC program diagram is set. An example of an AGC program diagram is shown in FIG. When any of S1032, S1033, and S1034 is executed, the subroutine of FIG. 5 is terminated, and the process proceeds to S1040 of FIG.

  In S1040 of FIG. 4, an imaging process is performed. Based on the gain and shutter speed set up to heretofore, the imaging element 102 is controlled for imaging. After imaging at the set shutter speed, a RAW image is output as described above, output to the image processing unit 118, and stored in the memory 117.

  In S1050 of FIG. 4, a proper exposure determination process is performed. As described above, the camera control unit 119 obtains a photometric value from the image processing unit 118, and calculates an evaluation value for determining whether or not the captured image is in an appropriate exposure state. It is determined whether the calculation result of the evaluation value is the same value as the target value of the preset evaluation value.

  In S1060 of FIG. 4, in response to the determination result in S1050, the exposure parameter is set to be the same as the evaluation value calculated in S1050 and the previously set target value. The EV value is shifted on the program diagram set in S1030 of FIG. 4, and the gain value, the shutter speed, the aperture value, etc. according to each EV value are set in each control unit 109-112.

  In S1070 of FIG. 4, communication is performed with the interchangeable lens 101 attached to the camera 100. The aperture value set in S1060 is reflected on the interchangeable lens 101 through the aperture controller 112. Further, the focal length information, the focus position information, the extender position information, the wide aperture value and the aperture value information of the interchangeable lens 101 are acquired. At this time, if the full aperture value can be acquired, the wide aperture value is stored, and the wide aperture value acquisition flag is set to true. If the full aperture value cannot be acquired, the wide aperture value acquisition flag is set to false. However, even if the aperture position cannot be acquired, if the aperture value obtained for the aperture value set for the interchangeable lens 101 is not reached, it is determined that the lens has reached the open end, and the aperture value acquisition enable / disable flag is set. Set to true. In addition, when an operation such as zoom or extender is performed and the focal length changes, a phenomenon called F drop occurs. In this case, since the full aperture value changes, the full aperture value acquisition permission flag is set to false.

  In S1080 of FIG. 4, program diagram position calculation is performed. FIG. 8 shows the subroutine of S1080.

  In S1081 of FIG. 8, it is determined whether or not the maximum aperture value of the interchangeable lens 101 can be acquired. If the open aperture value acquisition flag set in S1070 in FIG. 4 is true, the process proceeds to S1082, and if it is false, the process proceeds to S1083.

  In S1082 of FIG. 8, the aperture position is calculated. A formula for calculating the aperture position is shown in Formula (1). The open aperture value in equation (1) is the value acquired in S1070. The “close-side aperture value” is an aperture value that is closest to the “Close” side in the program diagram. That is, the ratio of the current aperture position when the open side is set to 100% in the movable range of the aperture mechanism on the program diagram is calculated.

Aperture position [%] = (| Current aperture position-Close side aperture value | × 100)
/ | Open aperture value-Close side aperture value | ... Formula (1)
In S1083 of FIG. 8, the aperture position is set to 100 [%]. In S1070, when the full aperture value cannot be acquired, it is determined that the operating range of the aperture value cannot be determined. At this time, it is determined that the obtained aperture value is not reliable, and the aperture position is set to 100 [%], so that when a program diagram position to be described later is calculated, the current position at the program diagram position is It is possible to grasp the minimum margin with the end position.

  In S1084 in FIG. 8, the gain position is calculated. A formula for calculating the gain position is shown in Formula (2). In the movable range of the gain value on the program diagram, the ratio of the current gain value when the maximum gain value is 100% is calculated.

Gain position [%] = (| Current gain value−Minimum gain value | × 100)
/ | Maximum gain value-Minimum gain value | ... Formula (2)
In S1085 of FIG. 8, the shutter position is calculated. A formula for calculating the shutter position is shown in Formula (3). Similar to the gain position, the ratio of the current shutter value when the longest shutter speed is 100% in the movable range of the shutter value on the program diagram is calculated. However, the shutter value is generally indicated in 1 / X second, and the correct shutter position cannot be calculated with the value as it is. Therefore, the current shutter value, the shortest shutter value, the longest shutter value, and the shortest shutter value may be converted into Tv values using -log2 (shutter speed) and the equation (3) may be used.

Shutter position [%] = (| current shutter value−shortest shutter value | × 100)
/ | Longest shutter value-shortest shutter value (3)
In S1086 of FIG. 8, the positions calculated in S1082 to S1085 are tabulated for each exposure mode, and the position on the program diagram is calculated. The subroutine of S1086 is shown in FIG.

  In S10861 in FIG. 9, the exposure mode is determined. If it is the Tv mode, the process proceeds to S10862, if it is the Av mode, the process proceeds to S10863, and if it is the AGC mode, the process proceeds to S10864.

  In S10862 of FIG. 9, the program diagram positions in the Tv mode are totaled. This calculation formula is shown in Formula (4).

Tv mode program diagram position = (gain position + diaphragm position) / 2 Equation (4)
In S10863 in FIG. 9, the program diagram positions in the Av mode are totaled. This calculation formula is shown in Formula (5).

Av mode program diagram position = (gain position + shutter position) / 2 Expression (5)
In S10864 of FIG. 9, the program diagram positions in the Av mode are totaled. This calculation formula is shown in Formula (5).

AGC mode program diagram position = gain position (6)
When any of S10862, S10863, and S10864 in FIG. 9 is executed, the subroutine in FIGS. 9 and 8 is terminated, and the process proceeds to S1090 in FIG.

  In S1090 of FIG. 4, the program diagram position is displayed. The program diagram position calculated in S1080 is displayed on the display unit 107 via the display I / F unit 106. The subroutine of S1090 is shown in FIG.

  In S1091 of FIG. 10, it is determined whether or not the open aperture value can be acquired, similar to S1081 of FIG. If the open aperture value acquisition flag set in S1070 of FIG. 4 is true, the process proceeds to S1092, and if it is false, the process proceeds to S1093.

  In S1092 of FIG. 10, it is determined whether or not the program diagram position calculated in S1086 of FIG. The value of range A may be an arbitrary range. For example, the range A is set to 10% to 90%. When the calculated program diagram position is outside the range A (less than 10% or greater than 900%), it can be determined that there is no more margin on the program diagram. If S1092 is true, the process proceeds to S1094, and if it is false, the process proceeds to S1095.

  In S1093 of FIG. 10, it is determined that the program diagram position calculated in S1080 is unreliable, and for example, a gray color is set as the display color setting without reliability. Program diagram position display described later is performed with the display color set here.

  In S1094 of FIG. 10, it is determined that the program diagram position calculated in S1080 is reliable and is located within the range A, and a normal display color (for example, white) is set.

  In S1095 of FIG. 10, the program diagram position calculated in S1080 is outside the range A, and a warning display color (for example, yellow or red) for displaying a warning to the user is set.

  In S1096 of FIG. 10, the program diagram position calculated in S1080 is displayed on the screen by the display color set in S1093 to S1095. A screen display example of the program diagram position is shown in FIG. The display color set in FIG. 10 changes the character display color of AE (75%) displayed in FIG. When S1096 is executed, the process proceeds to S1100 in FIG.

  In S1100 of FIG. 4, the video data is output from the external operation unit 123 as described above. At this time, various information displays including the display of the program diagram position of the video camera are superimposed on the video data.

  In this way, by switching the display color of the program diagram position in accordance with the reliability of the acquired aperture value, the user can visually recognize the reliability of the displayed program diagram position. Even if the full aperture value cannot be obtained from the interchangeable lens 101 attached to the camera 100, for example, the program diagram position in gray is displayed. In the present invention, since the program diagram position is calculated with the aperture position as 100%, the minimum margin for the maximum program diagram position in gray color can be guaranteed. Further, even if it is in the gray color display state, when the open end or the close end is reached in the process of controlling the aperture mechanism, the open aperture value acquisition availability flag becomes true as described in S1070, so that the white display Can be restored.

  As mentioned above, although preferable embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  It should be noted that the present invention can be applied even when the exposure modes described in this article are combined and the exposure mode is entirely automatic. Moreover, you may implement as automatic exposure including the ND control part 111. FIG.

  10 and 11 show display examples in which the program diagram position is indicated by characters, but a GUI (Graphical User Interface) using an indicator may be used as shown in FIG.

  In addition, when the zoom or extender is operated as described in S1070, the open aperture value acquisition flag is set to false, but the open aperture value of the attached interchangeable lens 101 is expressed by the following equation (7). Can be calculated. The program diagram position may be recalculated based on the calculated full aperture value. Note that the effective aperture is provided in the interchangeable lens 101 and is different for each lens. The effective aperture value may be acquired from the interchangeable lens 101, or may be stored in advance in a program or the like for each lens.

Open aperture value = focal length [mm] / effective aperture [mm] (7)
As mentioned above, although preferred embodiment for implementing this invention was described, this invention is not limited to the above-mentioned structure, It can apply to various embodiment and modification.

100 camera, 11 battery cover, 12 connector,
13 Access lamp, 28 Monitor, 29 Electronic viewfinder,
61 START / STOP button, 70 operation panel,
72 power / mode switch, 101 interchangeable lens, 102 image sensor,
103 ND unit, 104 recording medium I / F unit, 105 recording medium,
106 display I / F unit, 107 display unit, 108 focus detection unit,
109 gain control unit, 110 shutter control unit, 111 ND control unit,
112 Aperture control unit, 113 Focus control unit, 114 Image blur correction control unit,
115 GPU, 116 memory I / F unit, 117 memory, 118 image processing unit,
119 Camera control unit, 120 External output I / F unit, 121 External output unit,
122 I / F section for external operation, 123 External operation section, 124 Menu key,
125 cross key, 126 dial, 127 SET key,
128 cancel key, 129 one-shot AF key,
130 AF lock key, 131 Enlarge key, 132 DISPLAY key,
133 START / STOP key, 134 Focus ring,
135 AF / MF switch, 136 zoom control unit, 137 EXT state acquisition unit,
138 Zoom ring, 139 Servo / Manual switch,
140 EXT selector switch

Claims (6)

Imaging means for imaging a subject;
An optical device detachably attached to the imaging means and provided with a diaphragm mechanism;
Automatic exposure means for automatically adjusting the exposure based on an arbitrary program diagram for the subject imaged by the imaging means;
Diagram position information calculating means for calculating at which position in the program diagram the current exposure setting value set by the automatic exposure means;
A photographic apparatus comprising:
An open aperture value detection means for detecting an open aperture value of the aperture mechanism from the optical device;
Display means for displaying the diagram position information calculated by the diagram position information calculation means;
When the open aperture value can be detected by the open aperture value detection means, the diagram position information display means performs a diagram position display indicating a reliable value,
When the open aperture value cannot be obtained by the open aperture value detecting unit, the diagram position information display unit displays a diagram position indicating that the value is not reliable. .   In addition to the aperture mechanism, the optical device provided with a variable power lens mechanism, a focal length state detecting means for detecting that the focal length of the optical device has changed due to the operation of the variable power lens mechanism, and the focal length state The diagram position display indicating that the value is an unreliable value is performed by the diagram position information display unit when the detection unit detects that the focal length of the optical device has changed. The imaging apparatus according to 1.   When the open aperture value cannot be obtained by the open aperture value detection unit, the diagram position information calculation unit calculates the diagram position information with the current aperture position as the open end, and the diagram position information display unit The imaging apparatus according to claim 1 or 2, wherein a diagram position display indicating a value having no reliability is performed.   An effective aperture acquisition means for acquiring an effective aperture of the optical device from the optical device; an open aperture value is not obtained by the open aperture value detection means; a focal length of the optical device is obtained by the focal length state detection means; When the information changes, an open aperture value is calculated based on the amount of change in the focal length and the effective aperture, and the diagram position display is performed based on the calculated open aperture value. Item 3. The imaging device according to Item 2.   The imaging apparatus according to claim 2, wherein the zoom lens mechanism is a zoom lens.   The imaging apparatus according to claim 2, wherein the zoom lens mechanism is an extender.