JP2010197524A - Image capturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image capturing apparatus completely suppressing deterioration in image quality in movie shooting when an interchangeable lens that does not adapt to a high-speed communication system is used. <P>SOLUTION: When communication speed between a camera body 133 and the interchangeable lens 134 decreases, either a focus control value or a diaphragm control value is preferentially transmitted from the camera body 133 to the interchangeable lens 134 based on variation in the focus control value and the variation in the diaphragm control value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an imaging apparatus in which a camera body and an interchangeable lens perform data communication with each other.

  2. Description of the Related Art In recent years, image pickup elements have been increased in speed and performance, and it has become possible to acquire subject images at a high image pickup frame rate (the number of image data that can be taken per unit time). For this reason, imaging devices with interchangeable lenses have become more sophisticated and higher in image quality, and as with digital cameras, operations such as confirmation of the angle of view during shooting and fine focus adjustment can be performed on the display device. For this purpose, a live view function that displays the image formed on the image sensor as a moving image (through image) in real time on an LCD monitor, etc. A camera equipped with a shooting function that can be used has been developed.

  On the camera body side of the image-capturing apparatus with interchangeable lenses as described above, image data is generated for each frame by charges read at high speed from the image sensor at the time of live view display or moving image shooting, and in parallel therewith. It is necessary to send the control value of the optical element in the interchangeable lens to the interchangeable lens via the communication path for each frame. As the types of control values, there are a focus control value for controlling the position of the focus lens, an aperture control value for controlling the diameter of the aperture, and a zoom control value for continuously changing the zoom. As described above, it is necessary to send these control values to the interchangeable lens for each frame while synchronizing with the imaging timing of the imaging device. Therefore, when a high-speed image sensor is used to perform shooting at a high imaging frame rate, the traffic on the communication path (the number of communications per unit time) increases.

In view of such a current situation, there arises a problem that the communication method for transmitting the control value to the interchangeable lens must be changed to a faster method.
In order to solve this problem, for example, it is conceivable that a high-speed communication method suitable for a high imaging frame rate is simultaneously developed on the camera body side and the interchangeable lens side and mounted on the product.

  However, if the communication method of the old interchangeable lens that is already on the market does not support the high-speed communication method of the new camera body, high-speed data communication cannot be performed between the camera body and the interchangeable lens. In particular, particularly during moving image shooting in which focus control and aperture control are frequently performed, image quality degradation occurs due to poor focus and exposure control.

  Therefore, for example, when the focus control value is transmitted from the camera body to the interchangeable lens, the communication amount for focus control is reduced by changing the data length of the focus control value according to the focus control value, and focus control is performed. (For example, see Patent Document 1). In addition, there is an apparatus that sends a posture change amount detected on the interchangeable lens side to the camera body side and adjusts the white balance in accordance with the posture change amount on the camera body side (see, for example, Patent Document 2).

JP 2003-121722 A JP 2003-70006 A

  In Patent Document 1 described above, when an interchangeable lens that does not support a high-speed communication method is used, the communication amount for focus control can be reduced, but the communication amount for aperture control can be reduced. This is not possible, and the traffic on the communication path cannot be reduced sufficiently, so that it is not sufficient as a configuration for suppressing a reduction in image quality during moving image shooting.

  In the above-mentioned Patent Document 2, white balance can be adjusted in an image-capable imaging device, but when an interchangeable lens that does not support a high-speed communication method is used, the camera body and the interchangeable lens are used. High-speed data communication cannot be performed, and image quality deteriorates due to poor focus and exposure control during movie shooting.

  Therefore, an object of the present invention is to provide an imaging apparatus that can sufficiently suppress a deterioration in image quality during moving image shooting when an interchangeable lens that does not support a high-speed communication method is used.

  The imaging apparatus according to the present invention is an imaging apparatus in which a camera body and an interchangeable lens perform data communication with each other, and the interchangeable lens includes a focus lens that forms an image of an object on an image sensor in the camera body, and the imaging An aperture that adjusts the amount of light to the element, and the camera body includes an imaging unit that outputs a digital image corresponding to a subject image on the imaging element, and the aperture based on the digital image output from the imaging unit AE processing means for obtaining an aperture control value for controlling the diameter of the lens, AF processing means for obtaining a focus control value for controlling the position of the focus lens based on a digital image output from the imaging means, and a camera Communication path management means for managing a communication path between the main body and the interchangeable lens, and the communication path management means includes the camera body and the interchangeable lens. When the communication speed between drops, based on the variation amount of the variation amount and the focus control value of the iris control value, and sends either one of the aperture control value and the focus control value to preferentially the interchangeable lens.

  Further, the communication path managing means preferentially sends the focus control value to the interchangeable lens when the accumulated value of the fluctuation amount of the focus control value after normalization becomes a reference value or more, and the aperture after normalization When the accumulated value of the fluctuation amount of the control value becomes equal to or greater than the reference value, the aperture control value is preferentially sent to the interchangeable lens, the accumulated value of the fluctuation amount of the focus control value after normalization and the normalized value When the accumulated value of the fluctuation amount of the aperture control value is not equal to or more than the reference value, and when the fluctuation amount of the aperture control value after normalization is larger than the fluctuation amount of the focus control value after normalization, When the aperture control value is preferentially sent to the interchangeable lens, and both the accumulated value of the fluctuation amount of the focus control value after normalization and the accumulated value of the fluctuation amount of the aperture control value after normalization are not more than the reference value And normalization When the amount of variation of the aperture control value is not greater than the amount of variation of the focus control value after the normalization, the focus control values may be configured to send preferentially the interchangeable lens.

  In addition, the communication path management unit may change the imaging frame rate of the camera body when the cumulative value of the variation amount of the focus control value and the cumulative value of the variation amount of the aperture control value are equal to or greater than the reference value. It may be configured to change to an imaging frame rate corresponding to.

  Further, the AE processing means may be configured to control exposure using a program diagram that does not perform aperture control when the communication speed between the camera body and the interchangeable lens decreases.

  In addition, the communication path management means may change the aperture control value when the communication speed between the camera body and the interchangeable lens decreases and when the camera body is not panned or tilted. Then, based on the amount of change in the focus control value, either the aperture control value or the focus control value is preferentially sent to the interchangeable lens, and the communication speed between the camera body and the interchangeable lens decreases. In some cases, and when panning or tilting of the camera body is performed, the imaging frame rate of the camera body may be changed to an imaging frame rate corresponding to the interchangeable lens.

  According to the present invention, in an imaging apparatus in which a camera body and an interchangeable lens perform data communication with each other, even when an interchangeable lens that does not support a high-speed communication method is used, image quality deterioration during movie shooting is sufficiently suppressed. Can do.

1 is a diagram illustrating an overall configuration of an imaging apparatus according to a first embodiment of the present invention. It is a figure which shows a communication channel management part. 3 is a flowchart for explaining the operation of the imaging apparatus according to the first embodiment. It is a figure which shows an example of each time change of the aperture control value fluctuation | variation amount after normalization, and the focus control value fluctuation | variation amount after normalization. It is a flowchart for demonstrating other operation | movement of the imaging device of 1st Embodiment. It is a figure which shows the AE process part of the imaging device of 2nd Embodiment. It is a flowchart for demonstrating operation | movement of the imaging device of 2nd Embodiment. It is a figure which shows an example of the program diagram which performs aperture control. It is a figure which shows an example of the program diagram which does not perform aperture control. It is a flowchart for demonstrating operation | movement of the imaging device of 3rd Embodiment.

<First Embodiment>
FIG. 1 is a diagram illustrating an overall configuration of an imaging apparatus according to a first embodiment of the present invention. Note that the imaging apparatus according to the present embodiment is capable of capturing and displaying a moving image including a still image and a through image, and reproducing a still image and a moving image.

1 includes a camera body 133 and an interchangeable lens 134, and the camera body 133 and the interchangeable lens 134 perform data communication with each other via a communication path 126.
The interchangeable lens 134 communicates with the zoom lens 101, the zoom lens driving unit 102, the focus lens 103, the diaphragm 104, the focus lens driving unit 110, the diaphragm driving unit 111, the communication path 126, and the system controller 130. And a control unit 131.

The optical element of the interchangeable lens 134 includes a focus lens 103, a zoom lens 101, and a diaphragm 104.
The position of the focus lens 103 is controlled by the focus lens driving unit 110 so that light from the subject is imaged on the image sensor 106 of the camera body 133.

The focus lens driving unit 110 includes a motor and a motor driver, and driving is controlled by a focus control value obtained by the AF processing unit 116.
The zoom lens 101 changes the focal length between the focus lens 103 and the image sensor 106 when the position is controlled by the zoom lens driving unit 102.

  The zoom lens driving unit 102 includes a motor and a motor driver, and driving is controlled based on a zoom control value corresponding to the user's zoom operation information output from the UI control unit 121.

The diameter of the diaphragm 104 is adjusted by the diaphragm drive unit 111 to adjust the amount of light incident on the image sensor 106.
The aperture driving unit 111 includes a motor and a motor driver, and driving is controlled by an aperture control value obtained by the AE processing unit 115.

  The focus control value, the zoom control value, and the aperture control value are sent from the communication control unit 132 of the camera body 133 to the communication control unit 131 of the interchangeable lens 134 via the communication path 126 at a predetermined timing. .

  The camera body 133 includes a mechanical shutter 105, an image sensor 106, a CDS (correlated double sampling circuit) 107, an AMP 108, an A / D converter 109, a mechanical shutter driver 112, and an image sensor driver 113. The memory 114, the AE processing unit 115, the AF processing unit 116, the system controller 117, the image processing unit 118, the compression / decompression unit 119, the communication path management unit 120, the UI control unit 121, and the attitude detection unit. 122, a system bus 123, a display control unit 124, a recording medium control unit 125, an EVF 127, a recording medium 128, an LCD 129, and a communication control unit 132.

The UI control unit 121 receives input information from a user interface (not shown) operated by the user and outputs the input information to the system controller 117.
The image sensor 106 has a photoelectric surface in which a large number of light receiving elements are arranged in a matrix, and a subject image formed on the photoelectric surface is photoelectrically converted by the focus lens 103. Further, the image sensor 106 has RGB color filters arranged in a mosaic pattern. In addition, the image sensor 106 reads out the electric charges accumulated for each pixel in synchronization with the vertical transfer clock signal and the horizontal transfer clock signal supplied from the image sensor driving unit 113 and outputs them as an image signal. The exposure time of charges in each pixel is controlled by an electronic shutter drive signal given from the image sensor drive unit 113. The image signal output from the image sensor 106 is subjected to noise removal by the CDS 107 and gain adjustment, then amplified by the AMP 108, converted into image data as a digital signal by the A / D converter 109, and the memory 114. Temporarily written to.

The mechanical shutter 105 adjusts the exposure time of the image sensor 106 by the opening / closing operation being controlled by the mechanical shutter driving unit 112.
The mechanical shutter driving unit 112 includes a motor and a motor driver. When a pressing signal indicating that the shutter button has been pressed by the user is sent from the UI control unit 121 via the system controller 117, the system controller 117. Drive is controlled in accordance with the shutter control value output from. It is assumed that the mechanical shutter drive unit 112 does not operate during moving image shooting.

  The AF processing unit 116 obtains the in-focus position from the image data written in the memory 114 using the area information set by the UI control unit 121. Further, the AF processing unit 116 obtains in-focus positions for the image data continuously written in the memory 114 in accordance with the pressing signal sent from the UI control unit 121, and the focus lens 103 is based on the in-focus positions. A focus control value for controlling the position of is obtained.

  The AE processing unit 115 calculates the subject brightness from the image data written in the memory 114, and controls the shutter control value for controlling the opening / closing operation of the mechanical shutter 105 and the diameter of the aperture 104 based on the subject brightness. In addition to obtaining the aperture control value, etc., the white balance is adjusted.

  The image processing unit 118 performs image processing such as colorization, gamma correction, contrast correction, and edge enhancement on the image data written in the memory 114. When the image sensor 106 is a single-plate image sensor, colorization processing is necessary for image data captured by the image sensor 106. At this time, the image processing unit 118 generates a color signal by generating a luminance signal and a color difference signal from the single-plate image data by interpolation.

  The compression / decompression unit 119 performs compression processing on the image data subjected to the image processing by the image processing unit 118 in a compression format such as JPEG when shooting a still image and in a compression format such as MPEG when shooting a moving image. Generate an image file. The generated image file is written to the recording medium 128 controlled by the recording medium control unit 125. Further, the compression / decompression unit 119 reads the compressed image file from the recording medium 128 at the time of reproduction, and then performs decompression processing on the image file. The expanded image file is displayed on the EVF 127 or the LCD 129 controlled by the display control unit 124.

The display control unit 124 converts the image file read from the memory 114 and decompressed into a format that can be displayed on the EVF 127 or the LCD 129.
When displaying a through image, analog signal processing and digital conversion processing are performed at predetermined intervals on an image signal output from the image sensor 106, and image data is continuously generated. The image data is stored in the memory 114. Overwritten sequentially. Each image data sequentially overwritten in the memory 114 is displayed on the EVF 127 or the LCD 129 via the system bus 123 and the display control unit 124.

  Further, when a press signal is sent from the UI control unit 121 to the system controller 117 when a through image is displayed, the image data after image processing written in the memory 114 is compressed in a predetermined compression format by the compression / decompression unit 119. Is written to the recording medium 128. The image file written in the recording medium 128 is displayed on the EVF 127 or the LCD 129 after being decompressed by the compression / decompression unit 119 during reproduction.

FIG. 2 is a diagram illustrating the communication path management unit 120.
2 includes an aperture control value variation calculation unit 201, a focus control value variation calculation unit 202, a variation normalization unit 203, a lens information acquisition unit 204, and a communication band management unit. 205, a controller 206, and a priority order determination unit 207.

The aperture control value variation calculation unit 201 calculates the variation of the aperture control value obtained by the AE processing unit 115.
The focus control value fluctuation amount calculation unit 202 calculates the fluctuation amount of the focus control value obtained by the AF processing unit 116.

  The fluctuation amount normalizing unit 203 is normal with respect to the fluctuation amount of the aperture control value calculated by the aperture control value fluctuation amount calculating unit 201 and the fluctuation amount of the focus control value calculated by the focus control value fluctuation amount calculating unit 202. Do. For example, when the variation amount of the aperture control value and the variation amount of the focus control value are the functions f (t) at time t (t = 0, 1, 2,...), Respectively, The normalization of the variation amount of the control value and the variation amount of the focus control value may be obtained. Note that n is an integer larger than zero, and normalization of the variation amount of the aperture control value and the variation amount of the focus control value is performed in the range of t> n.

  The priority order determination unit 207 sends the focus control value and the aperture control value to the interchangeable lens 134 based on the normalized aperture control value variation and the normalized focus control value variation. Determine priority.

The communication band management unit 205 transmits the focus control value and the aperture control value to the interchangeable lens 134 with the priority determined by the priority determination unit 207.
The lens information acquisition unit 204 makes an inquiry about the lens type to the interchangeable lens 134 when the imaging apparatus is turned on or the interchangeable lens 134 is replaced, and holds the lens type obtained in response to the inquiry.

  The focus control value obtained by the AF processing unit 116 is sent from the communication control unit 132 on the camera body 133 side to the communication control unit 131 on the interchangeable lens 134 side via the communication path 126. The system controller 130 on the interchangeable lens 134 side controls the position of the focus lens 103 by controlling the driving of the focus lens driving unit 110 based on the focus control value sent to the communication control unit 131.

  The zoom operation information output from the UI control unit 121 is converted into a zoom control value by the system controller 117 of the camera main body 133, and then from the communication control unit 132 on the camera main body 133 side through the communication path 126 side. To the communication control unit 131. The system controller 130 on the interchangeable lens 134 side controls the position of the zoom lens 101 by controlling the driving of the zoom lens driving unit 102 based on the zoom control value sent to the communication control unit 131.

  The aperture control value obtained by the AE processing unit 115 is sent from the communication control unit 132 on the camera body 133 side to the communication control unit 131 on the interchangeable lens 134 side via the communication path 126. The system controller 130 on the interchangeable lens 134 side controls the diameter of the diaphragm 104 by controlling the driving of the diaphragm driving unit 111 based on the diaphragm control value sent to the communication control unit 131.

  Further, the system controller 117 controls the shutter speed of the mechanical shutter 105 by controlling the driving of the mechanical shutter driving unit 112 based on the shutter control value obtained by the AE processing unit 115.

FIG. 3 is a flowchart for explaining the operation of the imaging apparatus according to the first embodiment.
First, when a moving image shooting start instruction is sent from the UI control unit 121 to the system controller 117 by a user operation, the system controller 117 starts moving image shooting (S301).

  Next, the system controller 117 checks whether the interchangeable lens 134 is attached to the camera body 133 by controlling the operation of the lens information acquisition unit 204 via the controller 206 (S302).

When the interchangeable lens 134 is not attached (No in S302), the system controller 117 ends moving image shooting (S311).
On the other hand, when the interchangeable lens 134 is attached (Yes in S302), the system controller 117 makes an inquiry about the type of the interchangeable lens 134 by controlling the operation of the lens information acquisition unit 204 via the controller 206. The lens information acquisition unit 204 holds the type of the interchangeable lens 134 (S303).

  Next, the system controller 117 generates image data for obtaining the aperture control value and the focus control value by controlling the operations of the image sensor driving unit 113, the CDS 107, the AMP 108, and the A / D converter 109. Then, it is written in the memory 114 (S304).

Next, the system controller 117 obtains an aperture control value from the image data written in the memory 114 by controlling the operation of the AE processing unit 115 (S305).
Next, the system controller 117 obtains a focus control value from the image data written in the memory 114 by controlling the operation of the AF processing unit 116 (S306).

  Next, the system controller 117 controls the operation of the communication band management unit 205 via the controller 206 to determine whether or not the communication speed between the camera body 133 and the interchangeable lens 134 does not decrease (S307). ). That is, first, the communication band management unit 205 acquires an imaging frame rate A corresponding to the lens type of the interchangeable lens 134 from a table provided in the communication band management unit 205 or the like in advance. Next, the communication band management unit 205 acquires the currently set imaging frame rate B from the system controller 117. Then, the communication band management unit 205 determines whether or not the communication speed between the camera body 133 and the interchangeable lens 134 does not decrease based on the imaging frame rate A and the imaging frame rate B. For example, the communication band management unit 205 indicates that the maximum traffic value Bm of the communication path 126 when the moving image is captured at the imaging frame rate B is the traffic of the communication path 126 when the moving image is captured at the imaging frame rate A. You may determine by whether it is larger than the maximum value Am. At this time, when the maximum value Bm is larger than the maximum value Am, it is determined that the communication speed between the camera body 133 and the interchangeable lens 134 is decreased. On the other hand, when the maximum value Bm is not greater than the maximum value Am, it is determined that the communication speed between the camera body 133 and the interchangeable lens 134 does not decrease.

  When it is determined that the communication speed between the camera body 133 and the interchangeable lens 134 does not decrease (Yes in S307), an AE information transmission permission notification is sent from the communication band management unit 205 to the system controller 117. Then, the system controller 117 sends the aperture control value obtained by the AE processing unit 115 to the interchangeable lens 134 via the communication control unit 132 (S308), and the focus control value obtained by the AF processing unit 116 is sent to the communication control unit. It is sent to the interchangeable lens 134 via 132 (S309).

  On the other hand, when it is determined that the communication speed between the camera body 133 and the interchangeable lens 134 is decreased (No in S307), the system controller 117 controls the operation of the aperture control value variation calculation unit 201 via the controller 206. By doing this, the variation amount of the aperture control value that is the difference between the aperture control value obtained by the AE processing unit 115 in the current frame and the aperture control value obtained by the AE processing unit 115 one frame before is calculated ( S312).

  Next, the system controller 117 controls the operation of the focus control value fluctuation amount calculation unit 202 via the controller 206, so that the focus control value obtained by the AF processing unit 116 in the current frame and the AF one frame before A fluctuation amount of the focus control value that is a difference from the focus control value obtained by the processing unit 116 is calculated (S313).

  Next, the system controller 117 controls the operation of the fluctuation amount normalizing unit 203 via the controller 206, thereby changing the fluctuation amount of the aperture control value and the fluctuation amount of the focus control value, respectively, to predetermined arithmetic expressions (for example, the above-described values). Normalization is performed based on Equations 1 and 2), and the cumulative value of the variation amount of the aperture control value after normalization and the cumulative value of the variation amount of the focus control value after normalization are calculated (S314). The accumulated value of the fluctuation amount of the aperture control value after normalization is the total value of the fluctuation amount of the aperture control value after normalization obtained every time image data is generated, and the focus control value after normalization The accumulated value of the fluctuation amount is a total value of the fluctuation amounts of the normalized focus control value obtained each time image data is generated. In addition, it is assumed that the accumulated value of the variation amount of the aperture control value after normalization and the accumulated value of the variation amount of the focus control value after normalization are each initialized when the imaging apparatus is activated.

  Next, the system controller 117 controls the operation of the priority order determination unit 207 via the controller 206 so that the accumulated value of the fluctuation amount of the focus control value after normalization is equal to or larger than a predetermined reference value. It is determined whether or not (S318).

  When it is determined that the accumulated value of the fluctuation amount of the focus control value after normalization is equal to or greater than the reference value (Yes in S318), the AF order transmission permission notification is sent from the priority determination unit 207 to the system controller 117. Then, the system controller 117 sends the focus control value obtained by the AF processing unit 116 to the interchangeable lens 134 via the communication control unit 132 (S317), and prepares the normalized focus in preparation for the generation of the next image data. The accumulated value of the fluctuation amount of the control value is reset (S319).

  On the other hand, when it is determined that the accumulated value of the fluctuation amount of the focus control value after normalization is not greater than or equal to the reference value (No in S318), the system controller 117 controls the operation of the priority determination unit 207 via the controller 206. By doing so, it is determined whether or not the accumulated value of the fluctuation amount of the aperture control value after normalization is equal to or greater than the reference value (S320).

  When it is determined that the accumulated value of the fluctuation amount of the aperture control value after normalization is equal to or greater than the reference value (Yes in S320), an AE information transmission permission notification is sent from the priority determination unit 207 to the system controller 117. Then, the system controller 117 sends the aperture control value obtained by the AE processing unit 115 to the interchangeable lens 134 via the communication control unit 132 (S316), and prepares the normalized aperture for the next image data generation. The accumulated value of the fluctuation amount of the control value is reset (S321).

  When it is determined that the accumulated value of the fluctuation amount of the aperture control value after normalization is not equal to or greater than the reference value (No in S320), the system controller 117 controls the operation of the priority determination unit 207 via the controller 206. Thus, it is determined whether or not the variation amount of the aperture control value after normalization is larger than the variation amount of the focus control value after normalization (S315).

  When it is determined that the fluctuation amount of the normalized aperture control value is larger than the fluctuation amount of the normalized focus control value (Yes in S315), the priority determination unit 207 notifies the system controller 117 of AE information transmission permission. Will be sent. Then, the system controller 117 sends the aperture control value obtained by the AE processing unit 115 to the interchangeable lens 134 via the communication control unit 132 (S316).

  On the other hand, when it is determined that the fluctuation amount of the aperture control value after normalization is not larger than the fluctuation amount of the focus control value after normalization (No in S315), the priority determination unit 207 sends AF information to the system controller 117. A transmission permission notice is sent. Then, the system controller 117 sends the focus control value obtained by the AF processing unit 116 to the interchangeable lens 134 via the communication control unit 132 (S317).

Next, the system controller 117 determines whether or not there is a moving image shooting end instruction (S310).
When it is determined that there is an instruction to end moving image shooting (S310: Yes), the system controller 117 ends moving image shooting (S311).

On the other hand, when it is determined that there is no moving image shooting end instruction (S310: No), the system controller 117 returns to S304.
FIG. 4 shows an example of temporal variation of the variation amount of the aperture control value after normalization and the variation amount of the focus control value after normalization. The horizontal axis indicates time t, and the vertical axis indicates the amount of fluctuation of the aperture control value after normalization (dashed line) and the amount of fluctuation of the focus control value after normalization (solid line).

  In FIG. 4, since the fluctuation amount of the focus control value after normalization is large before time t1, the focus control priority is high and the focus control value is sent to the interchangeable lens 134 with high frequency. In addition, after time t1, since the amount of fluctuation of the normalized aperture control value is large, the priority of aperture control becomes high, and the aperture control value is sent to the interchangeable lens 134 at a high frequency.

  According to the imaging apparatus of the first embodiment, when the communication speed between the camera main body 133 and the interchangeable lens 134 decreases, the focus control value and the aperture value are controlled based on the focus control value variation amount and the aperture control value variation amount. Since either one of the control values is preferentially sent from the camera body 133 to the interchangeable lens 134, an interchangeable lens 134 that does not support a high-speed communication method is used to connect the camera body 133 and the interchangeable lens 134. Even when the communication speed decreases, an appropriate focus control value and aperture control value suitable for the shooting scene can be sent from the camera body 133 to the interchangeable lens 134, and image quality degradation during moving image shooting can be sufficiently suppressed. .

In the imaging apparatus according to the first embodiment, when the accumulated value of the fluctuation amount of the normalized focus control value is equal to or greater than the reference value, the focus control value is sent to the interchangeable lens 134, and the normalized aperture control value Since the aperture control value is sent to the interchangeable lens 134 when the cumulative value of the variation amount is equal to or greater than the reference value, the interchangeable lens is simply compared to the case where a control value having a large variation amount is sent to the interchangeable lens 134. The bias of the control value sent to 134 is eliminated, and stable image quality can be obtained during moving image shooting.
<Other first embodiment>
FIG. 5 is a flowchart for explaining another operation of the imaging apparatus according to the first embodiment.

The difference from the flowchart shown in FIG. 3 is that S322, S323, and S324 are performed between S314 and S315.
That is, the system controller 117 calculates the accumulated value of the variation amount of the normalized aperture control value and the accumulated value of the variation amount of the normalized focus control value (S314), and then the normalized aperture control value. It is determined whether or not the cumulative value of the fluctuation amount and the cumulative value of the fluctuation amount of the normalized focus control value are both equal to or greater than the reference value (S322).

  When it is determined that the accumulated value of the fluctuation amount of the normalized aperture control value and the accumulated value of the fluctuation value of the normalized focus control value are both equal to or greater than the reference value (Yes in S322), the system controller 117 The imaging frame rate A corresponding to the lens type held in the information acquisition unit 204 is acquired from the communication band management unit 205 (S323).

  Next, the system controller 117 sends the acquired imaging frame rate A to the imaging device driving unit 113, changes the current imaging frame rate B to the imaging frame rate A (S324), and then proceeds to S310.

  On the other hand, when both the accumulated value of the fluctuation amount of the aperture control value after normalization and the accumulated value of the fluctuation amount of the focus control value after normalization are not more than the reference value (No in S322), the system controller 117 proceeds to S318. .

  In the imaging device of the other first embodiment, similarly to the imaging device of the first embodiment, the interchangeable lens 134 that does not support a high-speed communication method is used to connect the camera body 133 and the interchangeable lens 134. Even when the communication speed decreases, an appropriate focus control value and aperture control value suitable for the shooting scene can be sent from the camera body 133 to the interchangeable lens 134, so that it is possible to sufficiently suppress deterioration in image quality during moving image shooting. .

Further, according to the imaging apparatus of the other first embodiment, when the accumulated value of the variation amount of the normalized aperture control value and the accumulated value of the variation amount of the normalized focus control value are both equal to or greater than the reference value, Since the current imaging frame rate B is changed to the imaging frame rate A corresponding to the lens type, the traffic on the communication path 126 exceeds the upper limit value and neither the focus control value nor the aperture control value can be sent to the interchangeable lens 134. Can be prevented.
<Second Embodiment>
FIG. 6 is a diagram illustrating the AE processing unit 115 in the imaging apparatus according to the second embodiment of the present invention. The overall configuration of the imaging device is the same as the overall configuration of the imaging device shown in FIG.

The AE processing unit 115 illustrated in FIG. 6 includes a communication band management unit 501, a photometry calculation unit 502, an exposure calculation unit 503, and a program diagram switching unit 504.
In the imaging device of the second embodiment, the difference from the imaging device of the first embodiment is that when it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 decreases, the camera body 133 and the interchangeable lens 134 In order to reduce the amount of data communication, exposure control data communication is not performed between the camera body 133 and the interchangeable lens 134.

FIG. 7 is a flowchart for explaining the operation of the imaging apparatus according to the second embodiment.
First, when a moving image shooting start instruction is sent from the UI control unit 121 to the system controller 117 by a user operation, the system controller 117 starts moving image shooting (S601).

  Next, the system controller 117 checks whether the interchangeable lens 134 is attached to the camera body 133 by controlling the operation of the lens information acquisition unit 204 via the controller 206 of the communication path management unit 120 (S602).

When the interchangeable lens 134 is not attached (No in S602), the system controller 117 ends moving image shooting (S614).
On the other hand, when the interchangeable lens 134 is attached (Yes in S602), the system controller 117 controls the operation of the lens information acquisition unit 204 via the controller 206 of the communication path management unit 120, thereby controlling the interchangeable lens 134. The type is inquired, and the type is stored in the lens information acquisition unit 204 (S603).

  Next, the system controller 117 controls whether or not the communication speed between the camera body 133 and the exchange camera 134 is lowered by controlling the operation of the communication band management unit 205 via the controller 206 of the communication path management unit 120. Is determined (S604). A series of determination operations of the communication band management unit 205 at this time may be the same as the determination operations of the communication band management unit 205 in S307 of FIG.

  When it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 does not decrease (Yes in S604), the system controller 117 sends a high-speed communication enable notification sent from the communication band management unit 205 to the AE processing unit. 115 is sent to the communication band management unit 501 to cause the program diagram switching unit 504 to select a program diagram for performing aperture control as exposure control (S605).

FIG. 8 is a diagram illustrating an example of a program diagram for performing aperture control.
In the program diagram shown in FIG. 8, the vertical axis of the upper graph indicates the sensitivity Sv of the image sensor 106, the horizontal axis of the upper graph indicates the exposure value Bv, and the vertical axis of the lower graph indicates the aperture value of the aperture 104. Av is shown, and the horizontal axis of the lower graph shows the shutter speed Tv set for the image sensor 106.

  The program diagram shown in FIG. 8 is for setting an appropriate exposure value Bv by controlling the aperture value Av while fixing the shutter speed Tv in the relationship of exposure value Bv + sensitivity Sv = aperture value Av + shutter speed Tv. Is.

  For example, when it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 does not decrease (S604: Yes), the program diagram switching unit 504 selects the program diagram shown in FIG.

  On the other hand, when it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 is reduced (No in S604), the system controller 117 sends a high-speed communication impossible notification sent from the communication band management unit 205 to the AE. The program is sent to the communication band management unit 501 of the processing unit 115, and the program diagram switching unit 504 is caused to select a program diagram for which aperture control is not performed as exposure control (S606).

FIG. 9 is a diagram illustrating an example of a program diagram in which aperture control is not performed.
In the program diagram shown in FIG. 9, the vertical axis of the upper graph indicates the sensitivity Sv of the image sensor 106, the horizontal axis of the upper graph indicates the exposure value Bv, and the vertical axis of the lower graph indicates the aperture value of the aperture 104. Av is shown, and the horizontal axis of the lower graph shows the shutter speed Tv set for the image sensor 106.

  The program diagram shown in FIG. 9 is for setting an appropriate exposure Bv by controlling the shutter speed Tv while fixing the aperture value Av in the relationship of exposure value Bv + sensitivity Sv = aperture value Av + shutter speed Tv. It is.

  For example, when it is determined that the communication speed between the camera body 133 and the exchange camera 134 is decreased (No in S604), the program diagram switching unit 504 selects the program diagram shown in FIG.

  Next, the system controller 117 generates image data for obtaining the aperture control value and the focus control value by controlling the operations of the image sensor driving unit 113, the CDS 107, the AMP 108, and the A / D converter 109. Then, it is written in the memory 114 (S607).

  Next, the system controller 117 calculates the exposure value Bv from the image data and the program diagram written in the memory 114 by controlling the operation of the photometry calculation unit 502 of the AE processing unit 115 via the controller 505. At the same time, by controlling the operation of the exposure calculation unit 503 of the AE processing unit 115 via the controller 505, an aperture control value or a shutter control value is obtained based on the exposure value Bv calculated by the photometry calculation unit 502 (S608). . At this time, when a program diagram for performing aperture control is selected, an appropriate aperture control value is obtained, and when a program diagram for which aperture control is not performed is selected, an appropriate shutter control value is obtained. .

Next, the system controller 117 obtains a focus control value from the image data written in the memory 114 by controlling the operation of the AF processing unit 116 (S609).
Next, the system controller 117 controls whether or not the communication speed between the camera body 133 and the exchange camera 134 is lowered by controlling the operation of the communication band management unit 205 via the controller 206 of the communication path management unit 120. Is determined (S610).

  When it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 does not decrease (Yes in S610), the system controller 117 uses the communication control unit 132 to obtain the aperture control value obtained in S608 via the interchangeable lens. 134 (S611).

  On the other hand, when it is determined that the communication speed between the camera body 133 and the replacement camera 134 is reduced (No in S610), the system controller 117 exchanges the focus control value obtained in S609 via the communication control unit 132. The image is sent to the lens 134 (S612). At this time, the system controller 117 sends the shutter control value obtained in S608 to the mechanical shutter driving unit 112.

Next, the system controller 117 determines whether or not there is a moving image shooting end instruction (S613).
When it is determined that there is an instruction to end moving image shooting (S613: Yes), the system controller 117 ends moving image shooting (S614).

On the other hand, when it is determined that there is no moving image shooting end instruction (S613: No), the system controller 117 returns to S607.
According to the imaging apparatus of the second embodiment, the aperture control is not performed when the communication speed between the camera body 133 and the interchangeable lens 134 decreases, so the interchangeable lens that does not support a high-speed communication method. Even if the communication speed between the camera body 133 and the interchangeable lens 134 is reduced using the 134, it is possible to perform appropriate focus control and exposure control suitable for the shooting scene, and sufficiently reduce the image quality during movie shooting. Can be suppressed.

In the imaging apparatus of the second embodiment, when the communication speed between the camera body 133 and the interchangeable camera 134 decreases, an appropriate exposure value Bv is obtained by controlling the shutter speed Tv while fixing the aperture value Av. The program diagram for setting is used, but when the communication speed between the camera body 133 and the exchange camera 134 decreases, the exposure value is adjusted by controlling the sensitivity Sv while fixing the aperture value Av. A configuration may be used in which a program diagram for setting the value Bv is used.
<Third Embodiment>
FIG. 10 is a flowchart for explaining the operation of the imaging apparatus according to the third embodiment. The overall configuration of the imaging device is the same as the overall configuration of the imaging device shown in FIG.

  First, when a moving image shooting start instruction is sent from the UI control unit 121 to the system controller 117 by a user operation, the system controller 117 starts moving image shooting (S801).

  Next, the system controller 117 checks whether the interchangeable lens 134 is attached to the camera body 133 by controlling the operation of the lens information acquisition unit 204 via the controller 206 of the communication path management unit 120 (S802).

When the interchangeable lens 134 is not attached (No in S802), the moving image shooting is terminated (S810).
On the other hand, when the interchangeable lens 134 is attached (Yes in S802), the system controller 117 controls the operation of the lens information acquisition unit 204 via the controller 206 of the communication path management unit 120, so The type is inquired, and the type is stored in the lens information acquisition unit 204 (S803).

  Next, the system controller 117 controls whether or not the communication speed between the camera body 133 and the exchange camera 134 is lowered by controlling the operation of the communication band management unit 205 via the controller 206 of the communication path management unit 120. Is determined (S804). A series of determination operations of the communication band management unit 205 at this time may be the same as the determination operations of the communication band management unit 205 in S307 of FIG.

  When it is determined that the communication speed between the camera body 133 and the interchangeable camera 134 does not decrease (Yes in S804), the system controller 117 determines that the image sensor driving unit 113, the CDS 107, the AMP 108, and the A / D converter 109 By controlling the respective operations, image data for obtaining the aperture control value and the focus control value is generated and written in the memory 114 (S811).

Next, the system controller 117 obtains an aperture control value from the image data written in the memory 114 by controlling the operation of the AE processing unit 115 (S812).
Next, the system controller 117 obtains a focus control value from the image data written in the memory 114 by controlling the operation of the AF processing unit 116 (S813).

  Next, the system controller 117 sends the aperture control value obtained in S812 to the interchangeable lens 134 via the communication control unit 132 (S814), and the focus control value obtained in S813 via the communication control unit 132. (S815).

Next, the system controller 117 determines whether or not there is a moving image shooting end instruction (S809).
When it is determined that there is a moving image shooting end instruction (S809: Yes), the system controller 117 ends moving image shooting (S810).

On the other hand, when it is determined that there is no moving image shooting end instruction (No in S809), the system controller 117 returns to S804.
In addition, when it is determined that the communication speed between the camera body 133 and the exchange camera 134 is decreased (No in S804), the system controller 117 controls operations such as a camera shake detection unit and a gyroscope in the posture detection unit 122. As a result, the horizontal movement amount and vertical movement amount of the imaging apparatus are acquired (S805).

Next, the system controller 117 determines whether panning or tilting is performed based on the acquired horizontal movement amount and vertical movement amount (S806).
When it is determined that panning or tilting is performed (Yes in S806), the system controller 117 acquires the imaging frame rate A corresponding to the lens type of the interchangeable lens 134 from the table provided in the communication band management unit 205. Then, the acquired imaging frame rate A is sent to the imaging element driving unit 113, and the current imaging frame rate B is changed to the imaging frame rate A (S809).

Thereafter, the same operations as in S811 to S815 and S808 described above are performed.
If it is determined that panning or tilting has not been performed (No in S806), the system controller 117 controls the operations of the image sensor driving unit 113, the CDS 107, the AMP 108, and the A / D converter 109. Thus, image data for obtaining the aperture control value and the focus control value is generated and written in the memory 114 (S816).

Next, the system controller 117 determines the aperture control value from the image data written in the memory 114 by controlling the operation of the AE processing unit 115 (S817).
Next, the system controller 117 obtains a focus control value from the image data written in the memory 114 by controlling the operation of the AF processing unit 116 (S818).

Thereafter, the same operations as S312 to S321 and S808 in FIG. 3 are performed.
In the imaging device of the third embodiment, similarly to the imaging device of the first embodiment, communication between the camera body 133 and the interchangeable lens 134 is performed using the interchangeable lens 134 that does not support a high-speed communication method. Even if the speed drops, an appropriate focus control value and aperture control value suitable for the shooting scene can be sent from the camera body 133 to the interchangeable lens 134, so that it is possible to sufficiently suppress deterioration in image quality during moving image shooting.

  Further, according to the imaging device of the third embodiment, when panning or tilting is performed in the imaging device, the current imaging frame rate B is changed to the imaging frame rate A corresponding to the lens type. Even when panning or tilting is frequently performed in which focus control and aperture control are frequently performed, it is possible to prevent the traffic on the communication path 126 from exceeding the upper limit value so that neither the focus control value nor the aperture control value is delayed from the interchangeable lens 134. it can.

DESCRIPTION OF SYMBOLS 101 Zoom lens 102 Zoom lens drive part 103 Focus lens 104 Aperture 105 Mechanical shutter 106 Image pick-up element 107 CDS
108 AMP
109 A / D converter 110 Focus lens driving unit 111 Aperture driving unit 112 Mechanical shutter driving unit 113 Image sensor driving unit 114 Memory 115 AE processing unit 116 AF processing unit 117 System controller 118 Image processing unit 119 Compression / decompression unit 120 Communication path management Unit 121 UI control unit 122 attitude detection unit 123 system bus 124 display control unit 125 recording medium control unit 126 communication path 127 EVF
128 recording media 129 LCD
130. System controller 131 Communication control unit 132 Communication control unit 133 Camera body 134 Interchangeable lens An image pickup apparatus.

Claims (5)

An imaging device in which a camera body and an interchangeable lens perform data communication with each other,
The interchangeable lens is
A focus lens that forms an image of a subject on an image sensor in the camera body;
A diaphragm for adjusting the amount of light to the image sensor;
With
The camera body is
Imaging means for outputting a digital image corresponding to a subject image on the imaging element;
AE processing means for obtaining a diaphragm control value for controlling the diameter of the diaphragm based on a digital image output from the imaging means;
AF processing means for obtaining a focus control value for controlling the position of the focus lens based on a digital image output from the imaging means;
A communication path management means for managing a communication path between the camera body and the interchangeable lens;
With
When the communication speed between the camera body and the interchangeable lens decreases, the communication path management unit is configured to control the aperture control value and the focus based on the variation amount of the aperture control value and the variation amount of the focus control value. One of the control values is preferentially sent to the interchangeable lens. The imaging apparatus according to claim 1,
The communication path management means preferentially sends the focus control value to the interchangeable lens when the accumulated value of the fluctuation amount of the focus control value after normalization exceeds a reference value, and the aperture control value after normalization When the accumulated value of the fluctuation amount of the lens becomes equal to or greater than the reference value, the aperture control value is preferentially sent to the interchangeable lens, the accumulated value of the fluctuation amount of the focus control value after normalization and the aperture control after normalization When the cumulative value of the fluctuation amount of the value is not equal to or greater than the reference value, and when the fluctuation amount of the aperture control value after normalization is larger than the fluctuation amount of the focus control value after normalization, the aperture control When the value is preferentially sent to the interchangeable lens, and the accumulated value of the fluctuation amount of the focus control value after normalization and the accumulated value of the fluctuation amount of the aperture control value after normalization are not more than the reference value, And before normalization When the amount of variation of the aperture control value is not greater than the amount of variation of the focus control value after normalization, and sends the focus control value to preferentially the interchangeable lens,
An imaging apparatus characterized by that. The imaging apparatus according to claim 2,
The communication path management means corresponds to the imaging lens rate of the camera body corresponding to the interchangeable lens when the cumulative value of the variation amount of the focus control value and the cumulative value of the variation amount of the aperture control value are both equal to or greater than the reference value. The imaging device is characterized in that the imaging frame rate is changed. The imaging apparatus according to claim 1,
The imaging apparatus according to claim 1, wherein the AE processing unit controls exposure using a program diagram that does not perform aperture control when a communication speed between the camera body and the interchangeable lens decreases. The imaging apparatus according to claim 1,
When the communication speed between the camera body and the interchangeable lens drops and when the camera body is not panned or tilted, the communication path management means and the amount of change in the aperture control value and the Based on the fluctuation amount of the focus control value, either the aperture control value or the focus control value is preferentially sent to the interchangeable lens,
When the communication speed between the camera body and the interchangeable lens decreases and when the camera body is panned or tilted, the imaging frame rate of the camera body corresponds to the interchangeable lens. An imaging apparatus characterized by changing to a rate.