Camera

In a camera capable of setting an auto-bracketing photo-taking mode of photographing on a plurality of frames of a film continuously with a photo-taking exposure value changed automatically and stepwise, when the auto-bracketing photo-taking mode is set, photographing is performed with a predetermined standard exposure value on both of a start frame and an end frame of a continuous photo-taking in the auto-bracketing photo-taking mode, and photographing is performed with an exposure value different from the predetermined standard exposure value on a frame between the start frame and the end frame, so that the start frame and the end frame of the continuous photo-taking in the auto-bracketing photo-taking mode can be made to be photo-taking frames with the same exposure condition.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to a camera having an auto-bracketing
 photo-taking mode, capable of photographing on a plurality of frames of a
 film continuously with the photo-taking exposure value changed
 automatically and stepwise.
 2. Description of Related Art
 Conventionally, an auto-bracketing photo-taking mode of photographing on a
 plurality of frames of a film with the exposure value changed
 automatically has been used as a method for an automatic exposure control
 of a camera. According to the auto-bracketing photo-taking mode, in
 addition to photographs with the correct exposure, photographs
 intentionally with underexposure and overexposure can be obtained
 automatically and continuously.
 Recently, a film having a magnetic recording part has been available on the
 market. With a camera having a magnetic recording means for recording
 information on the magnetic recording part, various kinds of information
 concerning the photo-taking frames can be recorded on the film. According
 to the camera of this kind, which has a plurality of selective
 photo-taking modes capable of recording information selectively from
 plural kinds of information, or recording plural kinds of information at
 the same time, in a case where a specific photo-taking mode (the
 above-mentioned auto-bracketing photo-taking mode) is selected by a mode
 selecting means, information of commanding printing with the same
 condition (the same exposure amount and the same color filter are set) at
 the time of printing can be recorded with respect to each of the magnetic
 recording parts of a plurality of frames taken continuously according to
 the specific photo-taking mode by the magnetic recording means. The
 continuous photo-taking scenes having the information of commanding
 printing with the same condition are called "series scene".
 That is, the series scene stands for a series of photo-taking scenes to be
 printed with the same condition for accurately reproducing the exposure
 state at the time of photographing by prohibiting printing of the
 photo-taking frames with respective different exposures by an automatic
 printing photofinishing system. Therefore, information indicative of the
 series scene is recorded in the magnetic recording part of each
 photo-taking frame of the film, so that the plurality of frames with that
 information recorded can be printed with the same printing condition at
 the time of printing the film so as to obtain photographs as the
 photographer intended to have. This technique is disclosed in U.S. Pat.
 No. 5,027,140, etc.
 When the film having frames taken as the series scene as mentioned above is
 presented to a photofinishing laboratory for having photographs, even in a
 case where the automatic printing photofinishing system for executing
 printing exposure control automatically so as to have the correct exposure
 value for each frame taken ordinarily is used, since the magnetic
 recording part of the film has the series scene information recorded
 therein, the automatic printing photofinishing system reads the series
 scene information and processes the printing with the exposure amount and
 the color determination condition fixed, with respect to a plurality of
 continuous frames with the series scene set.
 Therefore, by recording information indicative of the series scene in the
 magnetic recording part of each of a series of photo-taking frames with
 intentional exposure shift taken with the auto-bracketing photo-taking
 mode, the film can be printed with the exposure intended by the
 photographer even in the case of the printing with the automatic printing
 photofinishing system.
 The information recorded on the magnetic recording parts of a plurality of
 frames taken continuously in the auto-bracketing photo-taking mode as the
 series scene does not include information indicative of which frame is of
 the correct exposure, or which frame is of the overexposure or the
 underexposure, but includes information indicating that each frame is a
 start frame, an end frame or an intermediate frame of the series scene.
 For example, in a case where a film in which the auto-bracketing
 photo-taking was performed in the order of the correct exposure, the
 underexposure and the overexposure is printed by the automatic printing
 photofinishing system in the same order, since the start frame of the
 series scene is taken with the correct exposure, the automatic printing
 photofinishing system gives the correct exposure value to this frame and
 prints the frames included in the series scene with the same condition, so
 that the prints with the exposure shift intended by the photographer can
 be obtained.
 However, there are various kinds of automatic printing photofinishing
 systems and the order of developing a film varies depending on the kind of
 the automatic printing photofinishing system. Therefore, in a case where
 the automatic printing photofinishing system does not print in the same
 order, that is, in a case where the automatic printing photofinishing
 system prints in the reverse order, the printing operation is executed
 from the end frame of the series scene, so that the exposure value is
 given such that the end frame has the correct exposure, and thus the
 series of the plurality of frames taken in the auto-bracketing
 photo-taking is printed with the exposure value different from the value
 intended by the photographer. In the case of a positive film with a narrow
 latitude, the exposure value cannot be made drastically different from
 that intended by the photographer due to the automatic exposure amount
 adjustment by the automatic printing photofinishing system, so that the
 above-mentioned phenomenon is not problematic for the photographer.
 However, in the case of a negative film with a wide latitude, since the
 exposure value in the printing step poses a great influence on the final
 printing finish, the abovementioned phenomenon is manifest remarkably.
 BRIEF SUMMARY OF THE INVENTION
 It is an object of the invention to provide a camera and a photographing
 apparatus capable of giving prints with an exposure changed stepwise as
 intended by a photographer, regardless of the kind of an automatic
 printing photofinishing system, even in a case where the film used in the
 auto-bracketing photo-taking mode is a negative film.
 To attain the above object, in accordance with one aspect of the invention,
 there is provided a camera comprising photo-taking mode setting means for
 setting one of photo-taking modes of the camera, the photo-taking modes
 including an auto-bracketing photo-taking mode of photographing on a
 plurality of frames of a film continuously with a photo-taking exposure
 value changed automatically and stepwise, and photo-taking control means
 for, when the auto-bracketing photo-taking mode is set by the photo-taking
 mode setting means, photographing with a predetermined standard exposure
 value on both of a start frame and an end frame of a continuous
 photo-taking in the auto-bracketing photo-taking mode, and photographing
 with an exposure value different from the predetermined standard exposure
 value on a frame between the start frame and the end frame, so that the
 start frame and the end frame of the continuous photo-taking in the
 auto-bracketing photo-taking mode can be made to be photo-taking frames
 with the same exposure condition.
 The above and further objects and features of the invention will become
 apparent from the following detailed description of a preferred embodiment
 thereof taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION
 Hereinafter, a preferable embodiment of the invention will be described in
 detail with reference to the drawings.
 FIG. 1 is a block diagram showing the circuit arrangement of a camera
 according to the embodiment of the invention. The arrangement of each part
 of the camera will be first described.
 In FIG. 1, reference numeral 1 denotes a microcomputer serving as a control
 device for controlling the entirety of the camera, reference numeral 2
 denotes a light measuring circuit for obtaining measured light information
 used for the decision of the exposure amount, reference numeral 3 denotes
 a distance measuring circuit for detecting the focal position so as to
 move a photo-taking lens to the focal position, reference numeral 4
 denotes a shutter control circuit for controlling opening/closing of the
 shutter, and reference numeral 5 denotes a diaphragm control circuit for
 controlling the aperture amount of the diaphragm of the lens. Reference
 numeral 6 denotes a display part provided outside the camera or inside the
 viewfinder for indicating various kinds of information such as the shutter
 speed and the aperture value. In a case where the series scene is set,
 information indicative of the series scene is displayed on the display
 part 6.
 Reference numeral 7 denotes a RAM serving as an external memory means,
 reference numeral 8 denotes an EEPROM serving as a nonvolatile external
 memory means, reference numeral 9 denotes a light-measuring and
 distance-measuring switch for starting measuring the light and distance
 (hereinafter referred to as the switch SW1), reference numeral 10 denotes
 a release switch for starting the shutter release operation (hereinafter
 referred to as the switch SW2), and reference numeral 11 denotes an
 auto-bracketing setting switch for setting the auto-bracketing
 photo-taking mode (hereinafter referred to as the switch BSW). Reference
 numeral 12 denotes an AE lock switch. Based on the measure light value
 obtained at the time when the AE lock switch 12 is pressed, the exposure
 value is decided. Reference numeral 13 denotes a setting dial for setting
 the automatic exposure shift amount of the auto-bracketing photo-taking by
 rotating the setting dial 13 with the switch BSW turned on, reference
 numeral 14 denotes a magnetic recording circuit for controlling a magnetic
 head 15 for writing photo-taking information on a film having a magnetic
 recording part, reference numeral 16 denotes a film detecting circuit for
 detecting the transport speed of the film and the position of the film
 according to a signal from a photo-sensor 19, reference numeral 18 denotes
 a film transport circuit for controlling a film transport motor 17 for
 transporting the film, reference numeral 20 denotes a film having a
 magnetic recording part, reference numeral 21 denotes a photo-sensor for
 reading out the film data from a data disk 22 provided at the film
 cartridge when the film cartridge is loaded in the camera, and reference
 numeral 23 denotes a film information detecting circuit for converting the
 output obtained from the photo-sensor 21 into information such as the kind
 and the sensitivity of the film.
 FIG. 2 is a flow chart showing the operation of the microcomputer 1 shown
 in FIG. 1. With reference to the flow chart of FIG. 2, the entire
 operation of the camera will be explained.
 When the main switch (not shown) is turned on, the microcomputer 1 starts
 the operation at a step 101.
 In the step 101, whether of not the film 20 is loaded in the camera is
 detected. If the film 20 is loaded, the photographing operation of a step
 102 and thereafter is executed. If the film 20 is not loaded, the
 photo-taking operation is prohibited so as to wait at this step until the
 film 20 is loaded. In the next step 102, whether or not the switch SW1 is
 on is judged. If the switch SW1 is on, the flow proceeds to a step 103 for
 starting measurement of the light and the distance. If the switch SW1 is
 not on, the flow returns to the step 102 so as to wait until the switch
 SW1 is turned on.
 In the next step 103, whether or not the auto-bracketing photo-taking mode
 is set by the switch BSW and the setting dial 13. If the auto-bracketing
 photo-taking mode is set, the flow proceeds to a step 104. If the
 auto-bracketing photo-taking mode is not set, the flow proceeds to a step
 105. A method for setting the exposure value shift will be explained
 later. In a case where the flow proceeds to the step 105, since the camera
 is a normal photo-taking mode for only one frame, the exposure value
 designated by the photographer will be set.
 In the step 104, whether the loaded film is a negative film or a positive
 film is judged. If the loaded film is a negative film, a subroutine step
 107 to be described later is executed. If the loaded film is judged to be
 a positive film, a subroutine step 106 to be described later is executed.
 In the next step 108, the shutter speed and the aperture value are set so
 as to determine the exposure value based on the designated exposure value
 in the step 105 and the exposure shift amount in the subroutine step 107
 or 106, and then, the flow proceeds to a step 109. In the step 109, the
 distance measuring operation is executed by the distance measuring circuit
 3. By moving a lens (not shown), an object is brought into focus. In the
 subsequent step 110, whether or not the switch SW2 is on is judged. If the
 switch SW2 is not on, the flow returns to the step 102 so as to repeat the
 same operation. If the switch SW2 is on, the flow proceeds to a step 111
 for executing an exposure operation. That is, the diaphragm of the lens is
 stopped at the value determined in the step 108 by driving the diaphragm
 control circuit 5, the exposing operation is executed by controlling the
 shutter (not shown) at the shutter speed determined in the step 108 by
 driving the shutter control circuit 4, and the diaphragm (not shown) is
 released into the open state by driving the diaphragm control circuit 5 so
 as to finish the exposing operation. Then, the flow proceeds to a step
 112.
 In the step 112, the operation of winding up the film 20 by driving the
 film transport motor 17 via the film transport circuit 18 is started. In
 the next step 113, recording of the photo-taking data such as the date on
 the magnetic recording part of the film 20 is started by the magnetic head
 15 by driving the magnetic recording circuit 14. In a step 114, whether or
 not the photo-taking mode is the auto-bracketing photo-taking mode is
 judged. If the photo-taking mode is the auto-bracketing photo-taking mode,
 the flow proceeds to a step 115. If the photo-taking mode is not the
 auto-bracketing photo-taking mode, the flow proceeds to a step 120
 directly.
 The operation from the step 115 to a step 119 is a series of the work for
 recording a series-scene command code for commanding the printing with the
 same condition (the same exposure amount and the same color determination
 condition) in the magnetic recording part of the film 20.
 If, in the step 115, the present frame is judged to be the frame from which
 the auto-bracketing photo-taking is started, the flow proceeds to a step
 117 so as to write a code indicative of the series-scene start frame in
 the magnetic recording part of that frame. Moreover, if, in the step 116,
 the present frame is judged to be the frame at which the auto-bracketing
 photo-taking is ended, the flow proceeds to a step 118 so as to write a
 code indicative of the series-scene end frame in the magnetic recording
 part of that frame. If the present frame is judged to be "NO" in both of
 the steps 115 and 116, the flow proceeds to the step 119 so as to write a
 code indicative of the series-scene intermediate frame in the magnetic
 recording part of that frame. In the next step 120, all the magnetic
 recording data to be recorded are recorded in the film 20. After finishing
 the recording, the flow proceeds to a step 121. In the step 121, when it
 is detected by the film detecting circuit 16 and the photo-sensor 19 that
 the film 20 has been transported by one frame to reach a predetermined
 position, the film transport motor 17 is stopped via the film transport
 circuit 18 so as to finish the release operation. Then, the flow returns
 to the step 102 to wait for the next release operation.
 The subroutine step 107 in FIG. 2 will be explained with reference to the
 flow chart of FIG. 3. This step is a subroutine to be executed when the
 film is judged to be a negative film in the step 104 of FIG. 2.
 In a step 201 of FIG. 3, whether or not the present frame is the first
 frame after starting the auto-bracketing photo-taking is judged. If the
 present frame is the first frame, the flow proceeds to a step 202 so as to
 set the correct exposure value obtained based on the light measurement
 result obtained in the step 105. If not, the flow proceeds to a step 203,
 where whether or not the present frame is the second frame after starting
 the auto-bracketing photo-taking is judged. If the present frame is the
 second frame, the flow proceeds to a step 204 so as to set an
 underexposure value according to an exposure shift amount set by the
 setting of the auto-bracketing photo-taking mode to be later described.
 Moreover, if, in the next step 205, the present frame is judged to be the
 third frame after starting the auto-bracketing photo-taking, the flow
 proceeds to a step 206 so as to set an overexposure value according to the
 set exposure shift amount. The correct exposure value described in the
 explanation hereinafter is the one obtained based on the light measurement
 result in the same manner.
 If, in the step 205, the present frame is judged to be the fourth frame
 after starting the auto-bracketing photo-taking, the flow proceeds to a
 step 207 so as to set the correct exposure value, and further, the flow
 proceeds to a step 208 so as to clear the number of photo-taking frames
 for the auto-bracketing photo-taking.
 The subroutine step 106 shown in FIG. 2 will be explained with reference to
 the flow chart of FIG. 4. This step is the subroutine to be executed in a
 case where the film is judged to be a positive film in the step 104 of
 FIG. 2.
 In a step 301 of FIG. 4, whether or not the present frame is the first
 frame after starting the auto-bracketing photo-taking is judged. If the
 present frame is the first frame, the flow proceeds to a step 302 so as to
 set the correct exposure value. If not, the flow proceeds to a step 303,
 where whether or not the present frame is the second frame after starting
 the auto-bracketing photo-taking is judged. If the present frame is the
 second frame, the flow proceeds to a step 304 so as to set an
 underexposure value according to an exposure shift amount set by the
 setting of the auto-bracketing photo-taking mode to be later described.
 Moreover, if, in the step 303, the present frame is judged not to be the
 second frame after starting the auto-bracketing photo-taking, the flow
 proceeds to a step 305 so as to set an overexposure value according to the
 set exposure shift amount. Then, the flow proceeds to a step 306 so as to
 clear the number of photo-taking frames for the auto-bracketing
 photo-taking.
 With the exposure value set by the subroutine maintained, the flow proceeds
 to the step 108 of FIG. 2, as mentioned above.
 Then, how to set the auto-bracketing photo-taking mode will be explained
 with reference to the flow chart of FIG. 5.
 In a step 401 of FIG. 5, whether or not the switch BSW is on is judged. If
 the switch BSW is not on, the setting operation is ended. If the switch
 BSW is on, the flow proceeds to a step 402 so as to read the setting dial
 13 being operated. If, in the next step 403, it is judged that the setting
 dial 13 is not being rotated, the flow returns to the step 401. On the
 other hand, if it is judged that the setting dial 13 is being rotated, the
 flow proceeds to a step 404 so as to read out the amount of rotation of
 the setting dial 13. In the next step 405, even in a case where it is
 judged that the setting dial 13 is being rotated, if the result of reading
 after the rotation of the setting dial 13 has not changed from the result
 of reading before the rotation thereof, the flow returns to the step 401.
 If the result of reading after the rotation of the setting dial 13 has
 changed from the result of reading before the rotation thereof, the flow
 proceeds to a step 406 so as to store an exposure shift amount
 corresponding to the amount of rotation of the setting dial 13. Then, the
 flow returns to the step 401. If the setting is determined, the setting
 operation is ended by turning off the switch BSW.
 As mentioned above, by rotating the setting dial 13 with the switch BSW
 turned on, the auto-bracketing photo-taking mode can be set or canceled,
 and the exposure shift amount can be set.
 FIGS. 6 and 7 are diagrams for explaining the information on the series
 scene according to the auto-bracketing photo-taking, recorded on the film.
 The information is recorded on the magnetic recording part 31 of the film
 20.
 FIG. 6 is a diagram showing the photographing state of the film when the
 auto-bracketing photo-taking is performed with a negative film used as the
 film.
 The normal photo-taking has been executed until the frame 51. From the
 frame 52, the auto-bracketing photo-taking is started. Since the frame 52
 is the first frame after starting the auto-bracketing photo-taking, the
 frame 52 is taken with the correct exposure, and at the same time,
 information indicating that this frame is a series-scene start frame is
 recorded in the magnetic recording part 31. The frame 53 is taken with an
 underexposure according to the exposure shift amount set by the setting of
 the auto-bracketing photo-taking mode, and at the same time, information
 indicating that this frame is a series-scene intermediate frame is
 recorded in the magnetic recording part 31. Similarly, the frame 54 is
 taken with an overexposure according to the exposure shift amount set by
 the setting of the auto-bracketing photo-taking mode, and at the same
 time, information indicating that this frame is a series-scene
 intermediate frame is recorded in the magnetic recording part 31. The
 frame 55 is taken with the correct exposure as the last frame of the
 auto-bracketing photo-taking, and at the same time, information indicating
 that this frame is a series-scene end frame is recorded in the magnetic
 recording part 31. As mentioned above, a series of operations of the
 auto-bracketing photo-taking is completed after taking the above four
 frames.
 Incidentally, the frame 56 is taken as the normal photo-taking, but in some
 cases, a further different auto-bracketing photo-taking may be started.
 FIG. 7 is a diagram showing the photographing state of the film when the
 auto-bracketing photo-taking is performed with a positive film used as the
 film. The normal photo-taking has been executed until the frame 61. From
 the frame 62, the auto-bracketing photo-taking is started. Since the frame
 62 is the first frame after starting the auto-bracketing photo-taking, the
 frame 62 is taken with the correct exposure, and at the same time,
 information indicating that this frame is a series-scene start frame is
 recorded in the magnetic recording part 31. The frame 63 is taken with an
 underexposure according to the exposure shift amount set by the setting of
 the auto-bracketing photo-taking mode, and at the same time, information
 indicating that this frame is a series-scene intermediate frame is
 recorded in the magnetic recording part 31. The frame 64 is taken with an
 overexposure according to the setting shift amount as the last frame of
 the auto-bracket photo-taking, and at the same time, information
 indicating that this frame is a series-scene end frame is recorded in the
 magnetic recording part 31. As mentioned above, a series of operations of
 the auto-bracketing photo-taking is completed after taking the above three
 frames.
 Incidentally, the frame 65 is taken as the normal photo-taking, but in some
 cases, a further different auto-bracketing photo-taking may be started.
 According to the above-mentioned embodiment, in a case where the film used
 in the auto-bracketing photo-taking is a negative film, since the start
 frame and the end frame of frames continuously taken have the photo-taking
 exposure amount unchanged, that is, are made to be frames with the correct
 exposure (neither the underexposure nor the overexposure), as shown in
 FIG. 6. Therefore, even in a case where a film taken by the
 auto-bracketing photo-taking in the order of the correct exposure, the
 underexposure and the overexposure is printed by an automatic printing
 photofinishing system for printing in the reverse order, since the start
 frame is a frame with the correct exposure, the print with the exposure
 intended by the photographer can always be provided.
 Although the information on the film used is read automatically from the
 data disk in the above-described embodiment, a switch for inputting the
 information may be provided so as to detect the film information according
 to the state of the switch.
 It is needless to say that the present invention is not limited to the
 arrangement of the above-described embodiment, but can be embodied in any
 configuration as long as the functions shown in claims or the functions
 shown by the embodiment can be realized.
 In the above-described embodiment, whether or not the film used in the
 auto-bracketing photo-taking is a negative film or a positive film is
 detected at the time of the auto-bracketing photo-taking mode, and if the
 film is a negative film, the start frame and the end frame of frames
 continuously taken in the auto-bracketing photo-taking mode are taken with
 the photo-taking exposure amount unchanged, that is, with the correct
 exposure (neither the underexposure nor the overexposure), and the
 series-scene information commanding the print in the same condition so as
 to accurately reproduce the exposure state at the time the photographs are
 taken is recorded. However, it is not always necessary to record the
 series-scene information. For example, in the case of developing by the
 photographer himself or herself, or entrusting the print to a processing
 laboratory with the oral instruction not to use the automatic printing
 photofinishing system, the print with the exposure changed stepwise can
 also be obtained as intended by the photographer with the configuration
 that the photo-taking exposure amount unchanged for the start frame and
 the end frame of a negative film.
 Moreover, although the series-scene information is recorded magnetically in
 the above-mentioned embodiment, the series-scene information may also be
 recorded optically. Furthermore, although the information is recorded in
 the magnetic recording part of the film, the information may also be
 recorded in the film cartridge.
 Moreover, although the series-scene information is recorded in each of the
 auto-bracketing photo-taking frames, it is also possible that at least
 information of starting and ending the series scene is recorded in the
 start frame and the end frame of the auto-bracketing photo-taking.
 Furthermore, the present invention can be applied to various kinds of
 cameras such as lens-shutter cameras, single-lens reflex cameras, video
 cameras, electronic still cameras, or further, to photographing
 apparatuses adapted for the cameras, or elements constituting the same.
 As heretofore mentioned, according to the embodiments of the invention,
 there are provided a camera and a photographing apparatus capable of
 giving prints with an exposure changed stepwise as intended by a
 photographer even in a case where the film used in the auto-bracketing
 photo-taking mode is a negative film.
 Moreover, according to the embodiments of the invention, there are provided
 a camera and a photographing apparatus capable of giving prints with an
 exposure changed stepwise as intended by a photographer, regardless of the
 kind of an automatic printing photofinishing system, even in a case where
 the film used in the auto-bracketing photo-taking mode is a negative film.