JP4707590B2 - Imaging apparatus and imaging method - Google Patents

Description

  The present invention relates to an imaging apparatus having a macro function and an imaging method.

  2. Description of the Related Art Conventionally, there is a so-called macro function camera that switches between a normal shooting mode and a macro shooting mode with a switching button or the like. In this case, the photographer measures the distance to the subject in advance, determines which mode is used, and switches the mode with the switching button to perform shooting.

  In this shooting method, for example, when the normal shooting mode is selected and the subject is shot, if the subject distance is closer to the normal shooting distance than the normal shooting distance, that is, in the macro shooting area, it is outside the shooting range. An out-of-range warning is displayed. In the case of this out-of-range warning, the photographer is out of range, so the subject distance is set so that the subject distance is within the range, and this function is effective even though there is a function of macro shooting mode. It will be impossible to use.

  As conventional techniques for solving such problems, the inventions disclosed in Patent Documents 1 and 2 are known. According to Patent Document 1, when distance measurement information that is out of the macro shooting range and at a long distance is obtained in the macro mode, a release lock is performed and the macro mode is automatically released based on the release of the shutter button operation. In addition, an invention having switching means for automatically switching the lens from the macro position to the tele position is disclosed.

Further, in Patent Document 2, when distance measurement information indicating that photographing in the macro photographing mode is impossible is obtained in the macro photographing mode, the lens is driven from the macro position to the normal position. An invention is disclosed that includes a switching means for performing photographing and a returning means for returning the lens at the normal position to the macro position after the end of the normal photographing.
Japanese Patent No. 2750598 Japanese Patent No. 2767109

  However, in the above-described conventional technology, since the normal shooting mode and the macro shooting mode are switched by the manual switch operation, it is difficult to switch to the optimum shooting mode desired by the operator.

  In view of such a problem, the present invention automatically shifts to the shooting area in the macro shooting mode when the shift determining means determines that the shooting area has shifted from the shooting area in the normal shooting mode to the shooting area in the macro shooting mode. An object of the present invention is to provide an imaging apparatus and an imaging method that continue the distance measuring operation.

In order to achieve the above object, the present invention provides, as a first aspect, a distance measuring unit that measures an imaging distance to a subject, a normal shooting mode that measures a normal shooting area by the distance measuring unit, a macro mode for distance measurement of the macro region is a normal shooting area than the near shooting area, a switching means for switching the normal imaging mode and the macro-imaging mode, a distance measuring operation by the distance measuring means An imaging key for switching the imaging operation of the subject based on a pressed state of the key, an optical system for imaging the subject image at a predetermined position, and imaging the subject image input via the optical system An imaging unit that outputs image data, and the imaging unit scans the imaging area corresponding to each imaging mode, samples the evaluation value information of the subject, and detects a focus position. The in-focus position detecting means, the transition determining means for determining the transition of the photographing area in the normal photographing mode and the macro photographing mode, and the in-focus position detected by the in-focus position detecting means, If usually a closest position or outermost position close vicinity of the imaging area of the imaging mode, it is determined that the outside shooting range, on the basis of the evaluation value information, the photographing of the macro shooting mode to migrate Additional scanning range determining means for determining an additional scanning range for sampling the area, and the transition determining means determines transition from the imaging area in the normal imaging mode to the imaging area in the macro imaging mode. In this case, the distance measuring means automatically continues the distance measuring operation to the shooting area in the macro shooting mode.

In the imaging apparatus, it is preferable that the additional scanning range determination unit narrows the additional scanning range as the level of the evaluation value information on the in-focus position increases.

In the imaging apparatus, it is preferable that the additional scanning range determination unit narrows the additional scanning range as the change rate of the evaluation value information of the in-focus position increases.

According to a second aspect of the present invention, there is provided an imaging method of an imaging apparatus that switches between a ranging operation for measuring an imaging distance to a subject and an imaging operation for the subject based on a pressed state of a photography key. includes a normal mode for distance measurement normal shooting area, a macro mode for distance measurement of the macro region is a normal shooting area than the near shooting area, measuring the imaging distance up to the subject A ranging step, an imaging step of forming a subject image at a predetermined position using an optical system, capturing the subject image input via the optical system, and outputting image data; and In the step, the optical system scans the imaging region corresponding to each imaging mode, the evaluation value information of the subject is sampled, and an in-focus position detecting step for detecting an in-focus position, and the normal imaging mode And said ma The transition determination step for determining the transition of the shooting region in the shooting mode and the focus position detected in the focus position detection step are the closest position or the closest position in the shooting region in the normal shooting mode. when a position close vicinity, Ta is determined to be outside the shadow area, based on the evaluation value information, additional scanning range decision to determine additional scanning range for sampling the imaging area of the macro shooting mode to migrate And in the transition determining step, if it is determined that the transition from the shooting area in the normal shooting mode to the shooting area in the macro shooting mode is determined, in the ranging step, Provided is an imaging method characterized in that distance measurement is automatically continued to the imaging area in the macro imaging mode.

In the imaging method, additional scanning range determining step, as the level of the evaluation value information of the in-focus position is high, it is preferably characterized in that narrowing the additional scan range.

In the imaging method, additional scanning range determining step, as the rate of change of the evaluation value information of the in-focus position is high, it is preferably characterized in that narrowing the additional scan range.

According to the present invention, when the transition determining unit determines that the transition from the shooting area in the normal shooting mode to the shooting area in the macro shooting mode is performed, the distance measuring operation is automatically continued to the shooting area in the macro shooting mode. An imaging apparatus and an imaging method can be provided .

Hereinafter, an imaging apparatus and an imaging method of the present embodiment will be described in detail with reference to the drawings. In addition, this embodiment is not limited to what will be described later, and various modifications can be made without departing from the spirit of the present embodiment. Further, a description will be given using a digital camera as the imaging apparatus in the present embodiment.
FIG. 1 is a diagram schematically illustrating the appearance of a digital camera according to the present embodiment.

  The digital camera of this embodiment includes an LCD monitor 1, a sub LCD 2, an optical viewfinder 3, a strobe light emitting unit 4, a distance measuring unit 5, a remote control light receiving unit 6, a lens barrel unit 7, an SD card / battery. A lid 8, an autofocus LED 9, and a strobe LED 10 are provided.

  As various operation switches, a release shutter (SW1), a mode dial (SW2), a zoom switch (SW3), a self timer / deletion switch (SW4), a menu switch (SW5), and an up / strobe switch (SW6), right switch (SW7), down / macro switch (SW8), left / image confirmation switch (SW9), display switch (SW10), OK switch (SW11), and power switch (SW12) And.

  In FIG. 1, when the digital camera is viewed from the back, an autofocus LED 9 for informing the user that the focal length has been reached by autofocus (AF), a strobe LED 10 for informing the user of the completion of the strobe charging, and an optical viewfinder 3 and a zoom switch (SW3) for operating the zoom in the Tele direction or Wide direction. In addition, a power switch (SW12) for turning on / off the power of the main body, an LCD monitor 1 for displaying a monitoring image and a setting screen, other up / down / left / right switches, a frequently used self-timer There are switches and OK switches.

  When the digital camera is viewed from above, there are a release shutter (SW1), a mode dial (SW2) for switching between various shooting modes and playback modes, a sub LCD 2 for displaying the remaining number, battery end, and the like.

  Further, when the digital camera is viewed from above, there is an SD card / battery cover 8 for storing an external memory as a recording medium such as a battery or an SD card in the camera body. Further, there are a lens barrel unit 7 storing an imaging lens, a remote control light receiving unit 6, a distance measuring unit 5 for measuring a distance to a subject to realize autofocus, a strobe light emitting unit 4, and the like.

FIG. 2 is a block diagram showing the configuration of the digital camera of this embodiment.
As shown in FIG. 2, the digital camera 20 is capable of communicating with the printer 30 by using a USB or Bluetooth (Bluetooth (registered trademark)).

The digital camera 20 includes an external storage device 22 such as a flash memory that stores image information, an imaging unit 23 that is an image information input unit such as a CCD or an A / D converter, a display unit 24 that displays various types of information, An operation unit 25 that inputs data to the digital camera 20 and a communication I / F unit 26 that controls an interface with an external device (the printer 30 in FIG. 2) are provided. These are controlled by an overall control unit 21 that controls the entire digital camera 20.
The overall control unit 21 is configured by a known microcomputer including a CPU, ROM, RAM, input / output ports (I / O ports), bus lines for exchanging data with these, and the like.

Next, the digital camera of this embodiment will be described in more detail with reference to FIGS. 1 and 3.
FIG. 3 is a block diagram showing the digital camera of this embodiment in more detail.

  The lens barrel unit 7 includes a zoom optical system 71 including a zoom lens 71a for capturing an optical image of a subject and a zoom drive motor 71b, a focus optical system 72 as an optical system including a focus lens 72a and a focus drive motor 72b, A diaphragm unit 73 composed of a diaphragm 73a and a diaphragm motor 73b, a mechanical shutter unit 74 composed of a mechanical shutter 74a and a mechanical shutter motor 74b, and a motor driver 75 for driving each motor are provided.

  The motor driver 75 then receives a drive command from a CPU block 1043 provided in the digital still camera processor 104, which will be described later, based on an input from the remote control light receiving unit 6 and operation inputs of various operation switches (SW1 to SW13). The drive is controlled by.

  The ROM 108 stores a control program, parameters for control, and the like. These data are described in codes that can be decoded by the CPU block 1043. When the power of the digital camera is turned on, various control programs are loaded into a main memory (not shown). The CPU block 1043 controls the operation of each part of the digital camera according to the program. At the same time, data necessary for control and the like are temporarily stored in the RAM 107 and a local SRAM 1044 provided in a digital still camera processor 104 described later. By using a rewritable flash ROM in the ROM 108, it is possible to change the control program and parameters for control, and the version upgrade in the control function of the digital camera can be easily performed.

The CCD 101 is a solid-state imaging device for photoelectrically converting an optical image.
The F / E (front end) -IC 102 receives a CDS 1021 that performs correlated double sampling for removing image noise, an AGC 1022 that performs gain adjustment, an A / D 1023 that performs digital signal conversion, and a vertical synchronization signal (from a CCD1 control block 1041). Hereinafter, a TG 1024 supplied with a horizontal synchronization signal (hereinafter referred to as HD) and controlled by the CPU block 1043 is provided. The TG 1024 generates drive timing signals for the CCD 101 and the F / E-IC 102.

A digital still camera processor (hereinafter abbreviated as “processor”) 104 performs white balance setting and gamma setting on output data sent from the F / E-IC 102 via the CCD 101.
Further, as described above, the processor 104 has the CCD1 control block 1041, the CCD2 control block 1042, the CPU block 1043, the local SRAM 1044, the USB block 1045, the serial block 1046, the JPEG CODEC block 1047, and the RESIZE block. 1048, a TV signal display block 1049, and a memory card block 10410.

  The CCD1 control block 1041 supplies the VD signal and HD signal to the TG 1024 of the E / F-IC 102. The CCD2 control block 1042 converts the image data into luminance data / color difference data by filtering processing. The CPU block 1043 controls the operation of each part of the digital camera according to the present embodiment described above, and the local SRAM 1044 temporarily stores data necessary for this control.

  The USB block 1045 and the serial block 1046 respectively perform USB communication / serial communication with an external device such as a personal computer. The JPEG CODEC block 1047 performs compression / decompression of the image data converted into the JPEG format. The RESIZE block 1048 enlarges / reduces the size of the image data by interpolation processing. The TV signal display block 1049 converts the image data into a video signal for display on an external display device such as a liquid crystal monitor or a TV. A memory card block 10410 controls a memory card that records captured image data.

The SDRAM 103 temporarily stores image data when the processor 104 performs various processes on the image data.
The image data stored here is, for example, “RAW-RGB image data in a state in which white balance setting and gamma setting are performed in the CCD 1 signal processing block 1041 after fetching from the CCD 101 via the F / E-IC 102. ”,“ YUV image data ”in which luminance data / color difference data conversion has been performed in the CCD 2 control block 1042,“ JPEG image data ”that has been JPEG compressed in the JPEG CODEC block 1047, and the like.

  The memory card throttle 121 is a throttle for attaching a removable memory card to the digital camera body, and is controlled by the memory card block 10410. The built-in memory 120 is a memory for storing captured image data even when no memory card is mounted on the memory card throttle 121 described above.

  The LCD driver 117 is a drive circuit that drives the LCD monitor 1 described later, and also has a function of converting the video signal output from the TV signal display block 1049 into a signal for display on the LCD monitor 1. The LCD monitor 1 is a monitor for monitoring the state of a subject before photographing, confirming a photographed image, and displaying image data recorded in a memory card or the built-in memory 120 described above.

  The video AMP 118 is an amplifier for converting the impedance of the video signal output from the TV signal display block 1049 to 75Ω, and the video jack 119 is a jack for connecting to an external display device such as a TV.

  The USB connector 122 is a connector for performing USB connection with an external device such as a PC. The RS-232C connector 1232 is a connector for serial connection with an external device such as a personal computer, and is connected via the serial driver circuit 1231 that converts the output signal of the serial block 1046 described above.

  Further, the SUB-CPU 109 is a CPU in which ROM and RAM are built in one chip, and output signals from various operation switches (SW1 to SW13) and the remote control light receiving unit 6 are output to the CPU block 1043 as user operation information. To do. Also, the camera state output from the CPU block 1043 is converted into control signals for the sub LCD 2, AF LED 9, strobe LED 10, and buzzer 113 described later, and output.

  The sub LCD 2 is a display unit for displaying, for example, the number of shootable images. The LCD driver 111 is a drive circuit for driving the sub LCD 2 by the output signal from the SUB-CPU 109 described above.

  The AF LED 9 is an LED for displaying an in-focus state at the time of shooting, and the strobe LED 10 is an LED for representing a strobe charging state. The AF LED 9 and the strobe LED 10 may be used for another display application, for example, while a memory card is being accessed. Various operation switches (SW1 to SW13) are key circuits operated by the user, and the remote control light receiving unit 6 is a signal reception unit of the remote control transmitter operated by the user.

  The audio recording unit 115 includes a microphone 1153 to which a user inputs an audio signal, a microphone AMP 1152 that amplifies the input audio signal, and an audio recording circuit 1151 that records the amplified audio signal. The audio reproduction unit 116 also converts an audio reproduction circuit 1161 that converts a recorded audio signal into a signal that can be output from a speaker, an audio AMP 1162 that amplifies the converted audio signal and drives the speaker, and an audio signal. And an output speaker 1163.

  In the hill-climbing CCD-AF control, which will be described later, an integrated value of the luminance difference of adjacent pixels is obtained from the digital RGB signal captured in the CCD1 control block 1041 of the processor 104, and the integrated value of the luminance difference is focused. The AF evaluation value indicating the degree is used. When the subject is in focus, the outline of the subject is clear and the brightness difference between adjacent pixels increases, so the AF evaluation value increases.

  Also, in the out-of-focus state, the contour portion of the subject is blurred, so that the luminance difference between pixels is small, and the AF evaluation value is small. When the AF operation is performed, the AF evaluation values are sequentially acquired while moving the lens, and the lens is stopped with the position where the AF evaluation value is maximized, that is, the peak position as a focal point.

Next, an example of the operation of the imaging apparatus according to the present embodiment will be described with reference to the drawings.
FIG. 4 is a flowchart illustrating the operation of the imaging apparatus according to the present embodiment. In the present embodiment, the AF operation is performed by setting the release switch (shutter), which is a photographing key, to a half-pressed state.

  First, it is determined whether or not the release switch is half-pressed (step S101). If it is not half pressed (step S101 / No), it waits until the release switch is half pressed. If the release switch is half-pressed (step S101 / Yes), an AE operation is performed (step S102), and then an AF operation is started (step S103). This AF operation is a hill-climbing CCD-AF, and the AF evaluation value indicating the contrast (brightness or density histogram distribution) of the image signal output from the CCD on which the subject image is formed via the photographing lens is maximum. Detect the position that becomes.

FIG. 7 shows the relationship between the focus lens position and the AF evaluation value level.
In the normal photographing mode, a normal photographing region from near infinity to 30 cm is scanned with the CCD-AF, and an AF evaluation value is acquired. In this AF result, it is determined whether or not the position where the AF evaluation value is maximum is the closest position in the normal shooting mode or the vicinity thereof, that is, whether the position is out of the shooting range (step S104).

  When it is determined that it is out of the imaging range, that is, when the AF result is determined to be the closest position or the vicinity thereof (step S104 / No), a short distance warning state is entered, and the additional scanning range is set to the normal imaging mode. Is determined based on the AF evaluation value information in the vicinity of the near end of the image, and an additional scanning range in the macro area is determined (step S105). In the determination of the AF evaluation value information, if the evaluation value level is larger than a preset threshold value or the inclination (inclination) of the evaluation value graph is large, an additional scanning range is set to about 20 cm. (Step S106). On the other hand, if the evaluation value level is smaller than a preset threshold value or the gradient of the evaluation value graph is small, the additional scanning range is increased to about 10 cm (step S107). In this way, the AF process is started again within each added macro area (step S108), and the focus lens is moved to the focus (in-focus) position.

  If it is determined in step S104 described above that the image is within the shooting range, that is, if the short distance warning state is not set (step S104 / Yes), the focus lens is then moved to the position where the AF evaluation value is maximized. Move. At this time, it is determined whether or not the maximum AF evaluation value is equal to or lower than a preset low contrast determination threshold value, ie, a so-called low contrast state (distance measurement impossible state) (step S109). When the maximum value of the AF evaluation value is within the low contrast determination threshold, that is, when the distance measurement is possible (step S109 / Yes), the AF process is continued and the focus lens is moved to the focal position. And move. On the other hand, in the low contrast state, that is, in the state where distance measurement is impossible (step S109 / No), the AF processing result is NG, and the position corresponding to the hyperfocal distance, that is, the normal focal position (ordinary focal position) ) Move the focus lens to. In this embodiment, the normal focus position is 2.5 m.

The relationship between the focus lens position and the AF evaluation value level at this time will be described with reference to FIG.
FIG. 8 is a diagram illustrating an example of the relationship between the focus lens position and the AF evaluation value level according to the present embodiment. In FIG. 8, the horizontal axis indicates the focus lens position, and the vertical axis indicates the AF evaluation value level.

  FIG. 8A shows a case where the AF evaluation value level at the closest position (30 cm) in the normal imaging region is larger than the low contrast determination threshold and larger than the first level threshold. In this case, the additional scanning range is set to 1/3 of the macro imaging region.

  FIG. 8B shows a case where the AF evaluation value level at the closest position (30 cm) in the normal imaging region is larger than the low contrast determination threshold and smaller than the first level threshold. In this case, the additional scanning range is 2/3 of the macro photographing range.

  FIG. 8C shows that the AF evaluation value level at the closest position (30 cm) in the normal imaging region is larger than the low contrast determination threshold value, and the amount of change from the previous AF evaluation value is larger than the change amount threshold value. This also shows a large case. In this case, the additional scanning range is set to 1/3 of the macro imaging range.

  FIG. 8D shows that the AF evaluation value level at the closest position (30 cm) in the normal imaging region is larger than the low contrast determination threshold, and the amount of change from the previous AF evaluation value is larger than the amount of change threshold. Also shows a small case. In this case, the additional scanning range is 2/3 of the macro photographing range.

  FIG. 8E shows a case where the maximum AF evaluation value is smaller than the low contrast determination threshold. In this case, the additional scanning range cannot be set, and continuation to the macro area is prohibited.

  The AF evaluation value in the present embodiment varies from about 0 to 10,000 depending on the frequency component of the subject. The low contrast determination threshold is set as an intermediate value between the maximum value and the minimum value of a low-contrast subject such as a vertical stripe chart of about 5% shading, and the value is about 2000. The first threshold level is set as a value obtained by adding the minimum value to four times the amplitude difference (difference between the maximum value and the minimum value) in a low-contrast subject, and the value is about 5000. Further, the change amount of the AF evaluation value is about 1000 with respect to the change amount threshold value and the movement amount of the focus lens per unit.

  These values are determined from actually measured values. In this embodiment, the maximum position of the AF evaluation value is predicted from the AF evaluation value level or the amount of change at the closest position, and an appropriate scanning range is added. It becomes possible.

  Next, FIG. 5 is a flowchart showing an operation when the shooting mode is switched in the imaging apparatus of the present embodiment.

  First, when the macro switch is pressed, it is determined whether the current shooting mode is the normal shooting mode or the macro shooting mode (step S201). If the result of determination is that the current setting is normal shooting mode, the macro shooting mode setting operation is entered. In the macro shooting mode setting, the focus lens position is moved to the standby position in the macro area (step S202). In this embodiment, the focal length is equivalent to 30 cm. Furthermore, a macro mark is displayed on the liquid crystal display of the digital camera to indicate that the mode has been switched to the macro shooting mode (step S203).

  On the other hand, if the shooting mode when the macro switch is pressed is the macro mode, the normal shooting mode setting operation is started. In the normal shooting mode setting, the focus lens position is moved to the normal standby position (step S204). In this embodiment, it is equivalent to 2.5 m. Further, the macro mark is turned off on the liquid crystal display to indicate that the mode has been switched to the normal shooting mode (step S205).

  As described above, according to the imaging apparatus and the imaging method of the present embodiment, even when the subject position is in the macro area in the normal imaging mode, the imaging area in the macro imaging mode is automatically set without being aware of the photographer. The distance measuring operation can be continued. Therefore, troublesome operations such as mode switching are not required, and optimal focusing is possible.

Next, another example of the operation of the imaging apparatus according to the present embodiment will be described with reference to the drawings.
FIG. 6 is a flowchart illustrating the operation of the imaging apparatus according to the present embodiment. Also in this embodiment, the AF operation is performed by pressing the release switch halfway.

  First, it is determined whether or not the release switch has been half-pressed (step S301). If it is not half-pressed (step S301 / No), it waits until the release switch is half-pressed. If the release switch is half-pressed (step S301 / Yes), an AE operation is performed (step S302), and then an AF operation is started (step S303). This AF operation is a hill-climbing CCD-AF, and detects the position where the AF evaluation value indicating the contrast of the image signal output from the CCD on which the subject image is formed via the photographing lens is maximized.

The relationship between the focus lens position and the AF evaluation value level in this embodiment is the same as that shown in FIG.
In the normal photographing mode, a normal photographing region from near infinity to 30 cm is scanned with the CCD-AF to obtain an AF evaluation value. In this AF result, it is determined whether or not the position where the AF evaluation value is maximum is the closest position in the normal shooting mode or the vicinity thereof, that is, whether it is out of the shooting range (step S304).

  If it is determined that it is out of the imaging range, that is, if the AF result is determined to be at or near the nearest position (step S304 / No), a short distance warning state is entered, and an additional scanning range is set in the normal imaging mode. Is determined based on the AF evaluation value information in the vicinity of the near end of the image, and an additional scanning range in the macro area is determined (step S305). In the determination of the AF evaluation value information, if the evaluation value level is larger than a preset threshold value or the gradient of the evaluation value graph is large, the additional scanning range is reduced to about 20 cm. (Step S306). On the other hand, if the evaluation value level is smaller than a preset threshold value or the gradient of the evaluation value graph is small, the additional scanning range is increased to about 10 cm (step S307). In this way, AF processing is started again within each added macro area (step S308), and the focus lens is moved to the focus (focusing) position.

  If it is determined in step S304 that the image is within the shooting range, that is, if the short distance warning state is not set (step S304 / Yes), then the focus lens is placed at the position where the AF evaluation value is maximized. Move. At this time, it is determined whether or not the maximum AF evaluation value is equal to or lower than a preset low contrast determination threshold value, that is, a so-called low contrast state (distance measurement impossible state) (step S309). When the maximum value of the AF evaluation value is within the low contrast determination threshold value, that is, when the distance measurement is possible (step S309 / Yes), the AF process is continued as it is and the focus lens is moved to the focus position. And move. Up to this point, the operation is the same as that described with reference to FIG.

  On the other hand, in the case of the low contrast state (distance measurement impossible state) (step S309 / No), it is determined whether or not to move to the macro area according to the maximum evaluation value level. That is, here, evaluation value level determination is performed (step S310), and if the AF maximum evaluation value level is equal to or higher than the threshold for transition to the macro area, the macro area is set in the same manner as the short distance warning state in step S305. The AF operation is started again. At this time, the additional scanning range scans the entire macro area where the distance measurement is up to 1 cm.

  Further, when the AF maximum evaluation value level is equal to or less than the transition threshold value to the macro area, the focus processing lens is set to a position corresponding to the hyperfocal distance, that is, a normal focal position (ordinary focal position), with the AF processing result being NG. Move. In this embodiment, the normal focus position is 2.5 m.

The relationship between the focus lens position and the AF evaluation value level at this time will be described with reference to FIG.
FIG. 9 is a diagram illustrating another example of the relationship between the focus lens position and the AF evaluation value level according to the present embodiment. In FIG. 9, the horizontal axis indicates the focus lens position, and the vertical axis indicates the AF evaluation value level.

  FIG. 9 shows a case where the maximum AF evaluation value is smaller than the low contrast determination threshold and the maximum AF evaluation value is larger than the second level threshold. In this case, the additional scanning range is the entire macro imaging region.

  The AF evaluation value in the present embodiment varies from about 0 to 10,000 depending on the frequency component of the subject. The low contrast determination threshold is set as an intermediate value between the maximum value and the minimum value of a low-contrast subject such as a vertical stripe chart of about 5% shading, and the value is about 2000. The second threshold level is set as a minimum value for a low-contrast subject, and the value is about 1000.

  These values are determined from actually measured values. In this embodiment, the maximum position of the AF evaluation value is predicted from the AF evaluation value level or the amount of change at the closest position, and an appropriate scanning range is added. It becomes possible.

  As described above, according to the imaging apparatus and the imaging method of the present embodiment, even when the subject is not in the normal area but in the macro area, the camera automatically continues the ranging operation to the imaging area in the macro imaging mode. By doing so, an optimal scene can be shot.

  In addition, by determining whether to shift to the shooting area in the macro shooting mode or not when shooting outside the shooting range (short distance) in the shooting area in the normal shooting mode, it is possible to appropriately shift. Further, by making the shift determination only at the time of the warning, it is possible to reduce useless shift operations.

  It is also possible to shoot a subject in the vicinity of the closest position in the macro shooting mode by determining whether to shift to the shooting area in the macro shooting mode at the time of the non-distance measurement warning in the shooting area in the normal shooting mode. Is possible.

  In addition, when shifting to the shooting area in the macro shooting mode, the additional scanning range is made appropriate from the contrast information (evaluation value information) near the closest end in the normal area, so that the ranging operation in the useless area is performed. Without using it, the distance measurement time can be optimized.

  Furthermore, in a state where distance measurement is impossible due to low contrast, it is possible to reduce distance measurement operation to a useless macro area by determining whether or not to shift to a macro imaging mode imaging area based on low contrast information (evaluation value information). . In addition, when shifting, since the entire macro area is scanned, it is possible to shoot an object near the closest position in the macro shooting mode.

It is a figure which shows an example of the external appearance of the imaging device of this embodiment. It is a block diagram which shows the software structure of the imaging device of this embodiment. It is a block diagram which shows the structure of the imaging device of this embodiment. It is a flowchart which shows an example of AF operation | movement of this embodiment. 6 is a flowchart illustrating an operation when switching shooting modes in the imaging apparatus of the present embodiment. It is a flowchart which shows another example of AF operation | movement of this embodiment. It is a figure which shows the relationship between a focus lens position and AF evaluation value level. It is a figure which shows an example of the relationship between the focus lens position and AF evaluation value level in this embodiment. It is a figure which shows another example of the relationship between the focus lens position and AF evaluation value level in this embodiment.

Explanation of symbols

1 LCD monitor 2 Sub LCD
3 Optical viewfinder 4 Strobe light emitting unit 5 Ranging unit 6 Remote control light receiving unit 7 Lens barrel unit 8 SD card / battery cover 9 Autofocus LED
10 Strobe LED
20 Digital Camera 21 Overall Control Device SW1 Release Shutter SW2 Mode Dial SW3 Zoom Switch SW4 Self Timer / Delete Switch SW5 Menu Switch SW6 Up / Strobe Switch SW7 Right Switch SW8 Down / Macro Switch SW9 Left / Image Confirmation Switch SW10 Display Switch SW11 OK Switch SW12 Power switch

Claims (6)

Ranging means for measuring the imaging distance to the subject;
A normal shooting mode in which a normal shooting area is measured by the distance measuring means;
A macro mode for distance measurement of the macro region is a normal shooting area than the near shooting area,
Switching means for switching between the normal shooting mode and the macro shooting mode;
A shooting key for switching between a distance measuring operation by the distance measuring means and an imaging operation of the subject based on a pressed state of the key;
An optical system for forming a subject image at a predetermined position;
Imaging means for capturing the subject image input via the optical system and outputting image data;
In the imaging means, the optical system scans the imaging area corresponding to each imaging mode, the evaluation value information of the subject is sampled, and the in-focus position detecting means detects the in-focus position;
Transition determining means for determining transition of the photographing region in the normal photographing mode and the macro photographing mode;
The focus position detecting means is detected by that the alloy has focus position, wherein when the normal is closest position or outermost position close vicinity of the imaging area of the imaging mode, it is determined that the outside shooting range And an additional scanning range determination means for determining an additional scanning range for sampling the imaging region of the macro imaging mode to be shifted based on the evaluation value information,
When the transition determining means determines the transition from the shooting area in the normal shooting mode to the shooting area in the macro shooting mode, the distance measuring means automatically moves to the shooting area in the macro shooting mode. An imaging apparatus characterized by continuing the distance measuring operation.   The imaging apparatus according to claim 1, wherein the additional scanning range determination unit narrows the additional scanning range as the level of the evaluation value information of the in-focus position increases.   The imaging apparatus according to claim 1, wherein the additional scanning range determination unit narrows the additional scanning range as a change rate of the evaluation value information of the in-focus position increases. An imaging method of an imaging apparatus that switches between a ranging operation for measuring an imaging distance to a subject and an imaging operation for the subject based on a pressing state of a photography key,
With a normal shooting mode for distance measurement normal shooting area, a macro mode for distance measurement of the macro region is a normal shooting area than the near shooting area, measuring the imaging distance up to the subject Ranging process;
An imaging step of forming a subject image at a predetermined position using an optical system, capturing the subject image input via the optical system, and outputting image data;
In the imaging step, the optical system scans the imaging region corresponding to each imaging mode, the evaluation value information of the subject is sampled, and an in-focus position detecting step for detecting an in-focus position;
A transition determination step for determining transition of the photographing region in the normal photographing mode and the macro photographing mode;
The focus position detection process said detected focus position at the, wherein when the normal is closest position or outermost position close vicinity of the imaging area of the imaging mode, it is determined that the outside shooting range An additional scanning range determination step for determining an additional scanning range for sampling the imaging area of the macro imaging mode to be shifted based on the evaluation value information,
If it is determined in the transition determination step that the transition from the shooting region in the normal shooting mode to the shooting region in the macro shooting mode is determined, the shooting region in the macro shooting mode is determined in the ranging step. An imaging method characterized in that distance measurement is automatically continued.   5. The imaging method according to claim 4, wherein the additional scanning range determination step narrows the additional scanning range as the level of the evaluation value information at the in-focus position increases.   The imaging method according to claim 4, wherein the additional scanning range determination step narrows the additional scanning range as the change rate of the evaluation value information of the in-focus position increases.

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