JP2005260793A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a failure of photographing by reliably urging a warning that a high-sensitivity photographing mode is set. <P>SOLUTION: A photographer previously sets a method of representing a warning and executing conditions on a high-sensitivity warning setting screen displayed on an LCD panel 21. If a release button is operated by half depression in photographing a static image, in response to this, a set value of ISO sensitivity is detected to detect whether or not a digital camera is set at high sensitivity. If in high-sensitivity setting, it is determined whether or not a warning is performed on the basis of the predetermined condition, and the warning is represented by the predetermined display method corresponding to this determination result. The warning representation is performed by visual display for displaying a magnified icon 82a(82b) on an LCD panel 21 for a predetermined time or audio representation for emitting a warning message from a speaker. Performing such a warning representation causes the photographer to recognize that the digital camera is in a state of high-sensitivity set. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a digital camera capable of mode switching between a standard mode and a high-sensitivity shooting mode in which a subject is shot with higher sensitivity than the standard mode.

  2. Description of the Related Art Digital cameras that capture a subject image formed by an imaging optical system with a CCD image sensor or the like, generate image data from an imaging signal output from the CCD image sensor, and record the image data in a memory have become widespread. Unlike a film camera that prints an optical image on a photographic film, the digital camera has a function that can change the sensitivity of a captured image by performing settings on the camera body side. For example, when the light receiving sensitivity (hereinafter referred to as ISO sensitivity) of the image sensor is set by the photographer, the digital camera drives a CCD image sensor and captures a subject image with sensitivity according to the value of ISO sensitivity. Further, the sensitivity of the photographed image is changed by setting an amplification value that is a sensitivity corresponding to the ISO sensitivity value and amplifying the output signal of the CCD image sensor with this amplification value.

  By the way, most film cameras can perform shooting by switching between two shooting formats, standard and panorama. For photographs taken with the panorama shooting format (hereinafter abbreviated as panorama shooting), the top and bottom of the shot image obtained with the shooting in the standard shooting format (hereinafter abbreviated as standard shooting) are cut and panoramic format is obtained. The size of the When a high-sensitivity film with rough film particles is used for such panoramic photography, the enlargement ratio of the image is larger than that of the standard photograph, and the entire photograph is rough.

  In panoramic photography using a high-sensitivity film, it is necessary to urge the photographer to warn the photograph because the image quality of the photograph deteriorates due to enlargement of the photographed image. For example, in Patent Document 1, in response to an operation for switching to a panorama shooting format, the film sensitivity of a loaded film is detected, and if this film sensitivity is equal to or higher than a preset reference sensitivity, a panorama is displayed. A camera that issues a warning prohibiting switching to a recording format has been proposed.

  Even with digital cameras, when shooting bright scenes such as outdoors during the day with high sensitivity settings, noise will be present in the low-brightness part of the captured image (the part below the average average brightness) due to the deterioration of the S / N (Signal / Noize) ratio. As a result, the image quality deteriorates. For this reason, as in the case of a film camera, a digital camera having a function of issuing a warning at a high sensitivity setting has been proposed. For example, when the ISO sensitivity is set to high sensitivity, the icon is continuously displayed on the monitor. When the high sensitivity setting is selected and the shooting mode inappropriate for the high sensitivity setting is selected, the monitor is enlarged. There is a digital camera that visually displays a warning by displaying a displayed icon for a certain period of time. The photographer who sees the icon on the monitor notices that the high sensitivity is being set. When it is determined that high sensitivity setting is unnecessary in the current shooting scene, the ISO sensitivity is switched to a desired sensitivity.

JP-A-8-76238

  A digital camera that gives a warning by visual display as described above does not issue a warning with an impact that enlarges an icon immediately before or immediately after shooting. Therefore, even though the icon indicating the high sensitivity setting is displayed on the monitor, the photographer may take a picture without noticing that the high sensitivity setting is in progress, and the shooting may fail. It was.

  An object of the present invention is to provide a digital camera capable of reliably prompting a warning that a high sensitivity setting is being performed and preventing a photographing failure.

  The digital camera of the present invention can switch between a standard shooting mode and a high-sensitivity shooting mode in which a subject is shot with higher sensitivity than the standard shooting mode, and responds to a pressing operation of the shutter button. Whether or not the mode is switched to the high sensitivity shooting mode is identified, and a warning is displayed when the mode is switched to the high sensitivity shooting mode.

  The warning display may be performed in conjunction with the first-step pressing operation of the shutter button that determines the exposure condition at the time of shooting, or in conjunction with the second-step pressing operation of the shutter button that captures a still image of the subject. It may be performed as follows. The warning display is preferably performed by visual display on a display panel for displaying a finder image or a reproduced image, or auditory display by a speaker, and it is possible to set whether to use visual display or audio display. It is preferable. Further, when the mode is switched to the high-sensitivity shooting mode, it is preferable that a warning display is performed even when the power switch is turned on.

  According to the present invention, it is identified whether or not the mode is switched to the high-sensitivity shooting mode in response to the pressing operation of the shutter button, and the warning is displayed when the mode is switched to the high-sensitivity shooting mode. On the other hand, a warning that the high-sensitivity shooting mode is being set can be surely urged, and shooting failure can be prevented.

  Since either visual display or auditory display can be set, the operability of the digital camera can be improved.

  A digital camera 10 shown in FIG. 1 is provided with a lens barrel 12 in which a photographing lens is incorporated on the front surface of a main body 11, and a power switch 13 and a release button 14 are provided on the upper surface of the main body 11. The release button 14 is a two-stage pressing switch. When the release button 14 is lightly pressed and the first stage of the release button 14 is turned on (half-press), various functions such as focus adjustment and exposure adjustment of the photographing lens are performed. An imaging preparation process is performed. Next, when the release button 14 is pushed further deeply and the second stage of the release button 14 is turned on (fully pressed), an imaging process for recording still image data of a subject on a memory card based on an imaging signal obtained from a CCD image sensor. Is done.

  A finder eyepiece window 15, mode switch 16, general-purpose key 17, menu button 18, cancel button 19, display button 20, LCD panel 21, and speaker 22 are provided on the back of the main body 11. The viewfinder is an optical system viewfinder including an objective lens and an eyepiece. A warning lamp 23 is provided on the left side of the viewfinder eyepiece window 15 in the drawing. The photographer can check the lighting of the warning lamp 23 while looking through the viewfinder.

  The mode switch 16 switches between a shooting mode for performing an imaging process and a playback mode for playing back and displaying a recorded image on a memory card on an LCD (Liquid Crystal display) panel 21. The LCD panel 21 functions as an electronic viewfinder that displays a playback image in the playback mode and displays a through image for subject confirmation in the shooting mode. The LCD panel 21 displays a setting screen for performing various settings.

  When the menu button 18 is pressed, a setting screen is displayed on the LCD panel 21 and the mode is changed from the shooting mode or the reproduction mode to the setup mode. On this setting screen, items related to image quality adjustment, such as “Recording Pixels”, “ISO Sensitivity”, “Scene Select”, and items other than image quality adjustment, such as “Date / Time”, “Language”, “High Sensitivity Warning”, etc. Is set. The digital camera 10 operates according to the conditions set on this setting screen. The menu button 18 also functions as a confirmation / execution button for confirming or executing the selected item or process.

  The general-purpose key 17 functions as a cursor shift key for selecting an image to be reproduced or moving a cursor in the setting screen. The general-purpose key 17 includes a left shift key 17a and a right shift key 17c for moving the cursor in the left-right direction, and an up-down shift key 17b for moving in the up-down direction. Each of the left and right shift keys 17a, 17c is a push button type, and the up / down shift key 17b is provided so as to be swingable in the vertical direction around a horizontal axis. The up / down shift key 17b functions as a zoom button when operating in the shooting mode. The cancel button 19 cancels the selected item or operation. The display button 20 is a button for turning on / off the LCD panel 21.

  On the setting screen of “ISO sensitivity”, for example, selectable ISO sensitivities of “100”, “200”, “400”, “800”, “1600”, “AUTO” are displayed. In addition, on the setting screen of “Scene Select”, for example, shooting modes that can be selected from “Portrait”, “Landscape”, “Sports”, and “Night Scene” are displayed. In these selections, after the cursor is moved to select a desired item and the menu button 18 is pressed again, the selected content is confirmed and set. Then, the setting screen disappears from the LCD panel 21 and returns to the original screen.

  FIG. 2 is a block diagram showing an outline of the electrical configuration of the digital camera 10. The system controller 41 controls each part of the digital camera 10. The ROM 42 stores various screen data such as a control program and a setting screen. The system controller 41 performs control according to the steps described in the control program based on the operation signal input from the operation unit (release button 14, general-purpose key 17, menu button 18, etc.). The RAM 43 is a working memory for the system controller 41 to execute a control program.

  In the lens barrel 12, a photographing lens including a zoom lens 45 and a focus lens 46 and an aperture mechanism 47 are incorporated. The zoom lens 45 and the focus lens 46 are moved along the optical axis direction by a zoom motor 48 and a focus motor 49 provided with a driver circuit, and change in optical photographing magnification and focus adjustment are performed. The aperture mechanism 47 is driven by an actuator 50 having a driver circuit, and the aperture diameter is switched.

  A CCD image sensor 51 is disposed behind the focus lens 46. As is well known, the CCD image sensor 51 includes a photocathode in which a large number of light receiving elements are arranged in a matrix, and the subject light that passes through the photographing lenses 45 and 46 and the aperture mechanism 47 and forms an image on the photocathode. Is photoelectrically converted.

  The CCD image sensor 51 is driven by a CCD driver 52. The charge accumulation time (exposure time) of the CCD image sensor 51 is determined according to an electronic shutter drive signal supplied from the CCD driver 52 and determined based on the sensitivity selected on the “ISO sensitivity” setting screen. Then, in synchronization with the vertical transfer clock and the horizontal transfer clock supplied from the CCD driver 52, the charges accumulated for each pixel are output as a serial imaging signal line by line.

  The image pickup signal output from the CCD image sensor 51 is subjected to correlated double sampling processing to remove noise, and is input to the AD converter 54 via the amplifier 53. In the amplifier 53, an amplification value is set so as to achieve the sensitivity selected on the “ISO sensitivity” setting screen, and the imaging signal is amplified based on this amplification value. The A / D converter 54 digitally converts the amplified imaging signal to generate image data, which is input to the image data processing circuit 55.

  The image data processing circuit 55 performs various image processing such as matrix calculation processing, white balance adjustment, and gamma correction on the input image data. Image processed image data is temporarily stored in the frame memory 56. The LCD panel 21 outputs the image data stored in the frame memory 56 and displays a through image.

  When the imaging process is executed, the image data stored in the frame memory 56 is sent to the compression / decompression circuit 57. The compression / decompression circuit 57 performs a compression process on the image data and outputs it to the read / write circuit 58. The read / write circuit 58 writes the compressed image file to the memory card 59. In the reproduction mode, after the read / write circuit 58 reads the image file from the memory card 59, the decompression process is performed by the compression / decompression circuit 57 and the result is output to the LCD panel 21.

  The AF circuit 60 detects the focal position based on the image data stored in the frame memory 56. As a focus position detection method, for example, a passive method is used in which a focus position is detected by using a feature that the contrast of an image increases in a focused state.

  The AE / AWB circuit 61 measures the subject brightness based on the image data stored in the frame memory 56, and from this measured value, the aperture value, the exposure time, whether or not to emit a strobe (not shown), The white balance correction value is obtained by calculation.

  Exposure conditions such as the focus position, aperture value, and exposure time obtained by the AF circuit 60 and the AE / AWB circuit 61 are written into the RAM 43 by the system controller 41. The system controller 41 operates each unit based on the exposure conditions and the conditions set on the setting screen, and executes an imaging process.

  For example, the digital camera 10 is set to a standard sensitivity setting when the ISO sensitivity is set to a value smaller than “400”, and is set to a high sensitivity setting when set to “400” or more. When the release button 14 is pressed by the photographer, the ISO sensitivity setting value is detected in response to this, and it is determined whether or not the digital camera 10 is set to high sensitivity. In the case of the high sensitivity setting, a warning display that the digital camera 10 is in the high sensitivity setting is performed.

  The digital camera 10 is provided with a warning type setting memory 62. The warning type setting memory 62 has a “high sensitivity warning” setting screen (hereinafter referred to as a high sensitivity warning setting screen) on the LCD panel 21. Screen data for displaying is stored. The photographer can set a warning display method and execution conditions in the high sensitivity setting from the high sensitivity warning setting screen.

  The high sensitivity warning setting screen is composed of two sub screens 71 and 72. As shown in FIG. 3A, the sub screen 71 is a display method setting screen, as shown in FIG. 3B. The sub screen 72 is an execution condition setting screen. These two sub-screens 71 and 72 are selectively displayed. Tags for sub-screens that are not selected are grayed out and displayed. These sub screens 71 and 72 are switched by the left and right shift keys 17a and 17c.

  The sub screen 71 shows selectable display methods such as “icon”, “melody”, and “lamp”. A check box 73 is provided on the left side of each display method. The display method of warning is set by moving the cursor 74 and selecting any display method and checking the check box 73 of the corresponding display method. The photographer sets a plurality of display methods by the same operation.

  The contents of each display method will be described. When the “icon” is checked, an icon representing a warning is displayed on the LCD panel 21. When “voice” is checked, the warning sound generation circuit 64 is driven and a warning message is issued from the speaker 22. When the “lamp” is checked, the warning lamp 23 is turned on. When a plurality of display methods are checked, a plurality of warning displays are performed simultaneously.

  When the right shift key 17c is pressed while the cursor 74 is positioned on the checked display method, a detailed setting screen 75 for each display method is displayed on the right side of each display method. On this detailed setting screen 75, a display method for each display method is set. As shown in FIG. 3A, the icon detail setting screen 75 displays selectable icon display methods such as “enlarge”, “blink”, and “gradation”. The icon display method is set by moving the cursor 76 and selecting one of these.

  FIG. 4 shows a warning display when “icon” is selected as the display method and “enlarged” is selected as the display method of the selected “icon”. In this case, when the shooting mode is set by operating the mode change switch 16, the LCD panel 21 is automatically turned on, and a through image is displayed thereon. In addition to the through image, the LCD panel 21 displays an icon 82a (indicated by a dotted line in FIG. 4A) notifying that the high sensitivity is being set when the ISO sensitivity is high.

  In still image shooting, the subject 81a to be focused is placed in the center of the shooting frame, and the release button 14 is half-pressed in this state. At this time, the icon 82a becomes an icon 82b whose position is gradually enlarged and moved from the upper left to the center of the LCD panel 21. This icon 82b returns to the state of the original icon 82a (minimum size on the upper left of the LCD panel 21) when the state of FIG. Thereafter, as shown in FIG. 4B, the center of the photographing frame is aligned between the subject 81a and the subject 81b (framing), and the release button 14 is fully pressed to perform photographing. The time for which the icon 82b keeps the maximum size at the center of the LCD panel 21 can be set by the photographer and does not interfere with the framing.

  In FIG. 3B, the sub screen 72 displays selectable execution conditions such as “OFF”, “brightness setting”, “portrait”, “landscape”, “sports”, “night view”, for example. . The selection of each execution condition is performed by the cursor 78 in the same manner as the selection of the display method, and a check box 77 of a desired execution condition is checked to set the warning execution condition. Similar to the display method setting, a plurality of execution conditions can be set.

  The contents of each implementation condition will be described. When “OFF” is checked, the warning function itself in the high sensitivity setting is stopped, and the warning display is inevitably prohibited. When “brightness setting” is checked, it is determined whether or not to issue a warning according to the subject brightness based on the subject image data. The subject brightness is detected by the brightness detection circuit 63, for example. In response to an instruction from the system controller 41, the image data processing circuit 55 sends image processed image data to the luminance detection circuit 63. The luminance detection circuit 63 measures the subject luminance from the input image data, and sends a warning execution signal to the system controller 41 when the measured luminance value exceeds a preset reference luminance value. On the other hand, when the measured luminance value is equal to or lower than the reference luminance value, no warning execution signal is sent. When the digital camera 10 is set to high sensitivity and receives a warning execution signal from the luminance detection circuit 63, the system controller 41 issues a warning that the high sensitivity is being set by a preset display method.

  The implementation condition items “portrait”, “landscape”, “sports”, and “night view” all represent items of the shooting mode. When the digital camera 10 is set to high sensitivity and the shooting mode set in the execution condition is set, a warning display in the high sensitivity setting is performed. In the digital camera 10, for example, “sports” is set by default.

  Hereinafter, the operation of the above configuration will be described. The photographer sets in advance a warning display method and execution conditions in the high sensitivity setting. In setting the warning display method and execution conditions, first, a high sensitivity warning setting screen composed of the sub screens 71 and 72 is displayed on the LCD panel 21. The photographer selects “icon” and “melody” on the sub-screen 71 on which a plurality of display methods are displayed. As the display method of the selected “icon”, “enlarge” is selected (FIG. 3A). In addition, “brightness setting” is selected on the sub-screen 72 on which a plurality of execution conditions are displayed. In addition to “brightness setting”, “sports” is selected in advance as a default (FIG. 3B).

  When shooting a still image, first, the release button 14 is half-pressed by the photographer, and an exposure condition for performing an imaging process is set. Simultaneously with the setting of the exposure condition, it is determined whether or not the digital camera 10 has a high sensitivity setting. When the determination result is a high sensitivity setting, it is determined whether or not to display a warning based on a preset execution condition.

  When “brightness setting” and “sports” are set as the execution conditions, first, the current shooting mode is detected. When the sport mode is set as the current shooting mode, a warning is displayed. On the other hand, when a shooting mode other than the sport mode is set, the subject brightness is measured from the subject image data. When this measured luminance value exceeds the reference luminance value, a warning display is performed. On the other hand, when the measured luminance value is equal to or lower than the reference luminance value, no warning is displayed.

  The warning display is performed simultaneously by each preset display method. In the “icon” warning display, the icon 82a (82b) is enlarged and displayed on the LCD panel 21 for a certain period of time (FIG. 4A). In the “melody” warning display, a warning message is issued from the speaker 22. By displaying these warnings, the photographer recognizes that the digital camera 10 has a high sensitivity setting, and switches the ISO sensitivity if the high sensitivity setting is unnecessary in the shooting environment. Thereafter, when the release button 14 is fully pressed by the photographer, an imaging process is executed and a still image of the subject is recorded on the memory card 59.

  As described above, since the warning display in the high sensitivity setting is performed in response to the pressing operation of the release button 14, the photographer can surely recognize that the high sensitivity setting is being performed, and performs shooting without failure. be able to. In addition, it is possible to select at least one of visual display by the icon 82b (82b) and the warning lamp 23 and auditory display by the warning sound, and further, the execution conditions of the warning display can be selected. Operability can be improved.

  In the above embodiment, the warning display is performed by displaying the icon 82a (82b) on the LCD panel 21, but a character or an image may be displayed instead of the icon. Further, although the warning message is generated from the speaker 22, a warning sound such as a beep sound may be generated instead of the warning message.

  In the above-described embodiment, priority is given to the execution conditions “portrait”, “landscape”, “sports”, etc., and the current shooting mode is first detected and the shooting with the current shooting mode set as the execution condition. It is determined whether or not the mode corresponds to the mode, and then it is determined whether or not the subject luminance value based on the image data of the subject exceeds the reference luminance value. It is not limited.

  In the above embodiment, the warning display is performed in response to the half-pressing operation of the release button 14, but it may be performed in response to the full-pressing operation. In this case, the warning display may not be the same as that in the half-press operation. For example, the image data of the subject is displayed on the LCD panel 21 so that the low-luminance portion is automatically enlarged. This prompts the photographer to confirm the captured image data.

  In the above embodiment, the warning display is performed only once in response to the half-pressing operation of the release button 14, but the warning display is not limited to one time, and in addition to the half-pressing operation, The warning display may be performed in response to the operation for switching between the operation mode and the shooting mode.

  In the above embodiment, the shooting mode item is included in the execution condition, and a warning is displayed under the shooting mode set in the execution condition. However, the flash mode item may be included in addition to the shooting mode item. . Examples of the strobe mode items include “auto”, “forced flash”, and “slow sync”. In this case, for example, “forced light emission” may be set by default.

  In the above embodiment, the digital still camera that captures a still image has been described as an example, but the present invention may be applied to a video camera that records a moving image.

It is an external appearance perspective view of a digital camera. It is a block diagram which shows the electric constitution of a digital camera. It is explanatory drawing of a high sensitivity warning setting screen. It is explanatory drawing which shows the warning display of the display method "icon".

Explanation of symbols

10 Digital Camera 13 Power Switch 14 Release Button 16 Mode Change Switch 21 LCD Panel 22 Speaker 41 System Controller 62 Warning Type Setting Memory 71, 72 Sub Screen

Claims (6)

In digital cameras that can switch between standard shooting mode and high-sensitivity shooting mode where subjects are shot with higher sensitivity than standard shooting mode,
A digital camera that identifies whether or not the mode is switched to the high-sensitivity shooting mode in response to a pressing operation of a shutter button, and displays a warning when the mode is switched to the high-sensitivity shooting mode.   2. The digital camera according to claim 1, wherein the warning display is performed in conjunction with a first-stage pressing operation of a shutter button for determining an exposure condition at the time of photographing.   3. The digital camera according to claim 1, wherein the warning display is performed in conjunction with a second-stage pressing operation of a shutter button for photographing a still image of a subject.   4. The digital camera according to claim 1, wherein the warning display is performed by visual display on a display panel for displaying a finder image or a reproduced image, or by auditory display using a speaker.   The digital camera according to claim 4, wherein whether the visual display or the auditory display is used can be set.   The digital camera according to any one of claims 1 to 5, wherein the warning display is performed even when the power switch is turned on when the high-sensitivity shooting mode is switched.

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