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United States Patent4589754   
Link to this pagehttp://www.wikipatents.com/4589754.html
Inventor(s)Maitani; Yoshihisa (Hachioji, JP); Tsunefuji; Katsuhiko (Hachioji, JP); Yamasaki; Masafumi (Hachioji, JP)
AbstractA multi-mode camera is provided which permits a selection from among a plurality of photographing modes including an automatic mode, a manual mode, an average photometry mode and a spotwise photometry mode. The camera includes a photographing information display which is located within a finder and which is formed by a liquid crystal display panel. The display includes a plurality of display regions, which enable necessary and sufficient photographing information to be displayed within the finder during a particular photographing mode selected, by providing a bar representation in which display regions from one end of the display and extending to a point corresponding to photographing information are activated and providing a point display in which a selected display region is activated which corresponds to photographing information.
   














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Drawing from US Patent 4589754
Camera - US Patent 4589754 Drawing
Camera
Inventor     Maitani; Yoshihisa (Hachioji, JP); Tsunefuji; Katsuhiko (Hachioji, JP); Yamasaki; Masafumi (Hachioji, JP)
Owner/Assignee     Olympus Optical Co., Ltd. (Tokyo, JP)
Patent assignment
All assignments
Company News
Publication Date     May 20, 1986
Application Number     06/485,432
PAIR File History     Application Data   Transaction History
Image File Wrapper   Patent Term   Fees
Litigation
Filing Date     April 15, 1983
US Classification     396/290 396/296
Int'l Classification     G03B 017/20
Examiner     Perkey; William B.
Assistant Examiner    
Attorney/Law Firm     Weinstein; Louis
Address
Parent Case    
Priority Data     Apr 21, 1982[JP]57-65385
USPTO Field of Search     354/429 354/433 354/434 354/465 354/471 354/472 354/473 354/474 354/475 354/481 354/431 354/432 354/289.1 354/289.12 354/412 354/410 356/215 356/218 356/221 356/222 356/223 356/226 356/227
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ReferenceRelevancyCommentsReferenceRelevancyComments
4453811
Yamasaki
396/238
Jun,1984

[0 after 0 votes]
4401386
Yuasa
356/226
Aug,1983

[0 after 0 votes]
4309090
Yamada
396/233
Jan,1982

[0 after 0 votes]
4176955
Yamada
356/222
Dec,1979

[0 after 0 votes]
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What is claimed is:

1. A camera including selection means which permits a selection among a plurality of photographing modes which may include an automatic mode, a manual mode, an average photometry mode and a spotwise photometry mode; comprising:

a photographing information display located within the viewfinder of the camera and including fixed photographing indicia and a plurality of display elements which are arranged in linear succession;

means for activating those display elements of the display which begins at a display region located at one end of the display and extends to another location in the display corresponding to one of said indicia for representing photographing information, thereby displaying photographing information in a bar-like form;

and means responsive to a mode changing operation by said selection means for indicating such mode changing, once devativting all of said display elements and subsequently activating those display elements which begin from the display region located at one end of the display to a further location in said display corresponding to photographing information which is to be used in the new photographing mode.

2. A camera including selection means which permits a selection among a plurality of photographing modes including an automatic mode, a manual mode, an average photometry mode and a spotwise photometry mode; comprising:

a photographing information display located within a finder of the camera and including a plurality of diplay elements which are arranged in linear succession,

means for activating those display elements of the display which begins at a display region located at one end of the display and extends to another location in the display corresponding to photographing information, thereby displaying photographing information in a bar-like form;

means responsive to a mode changing operation by said selection means for indicating such mode changing, by one deactivating all of said display elements and subsequently activating those display elements which begin from the display region located at one end of the display to a further location in said display corresponding to photographing information which is to be used in the new photographing mode;

spotwise photometric means being energized responsive to selection of the spotwise photometry mode to permit a photographing operation in the spotwise photometry mode;

means for calculating a brightness value responsive to said spotwise photometric means;

exposure correction means for providing a correction of an exposure factor;

said display including means for displaying the brightness values obtained without any correction and for displaying an exposure factor incorporating the correction generated by the exposure correction means;

average photometric means being energized responsive to selection of the average photometry mode to permit a photographing operation in the average photometry mode; and

means for automatically changing the photographing mode from the spotwise mode to the average mode in response to completion of a photographing operation in the spotwise ode.
 Description Submit all comments and votes
 


BACKGROUND OF THE INVENTION

The invention relates to a photographic camera, and more particularly, to a camera which permits a selection among a plurality of photographing modes including an automatic exposure mode, a manual exposure mode, an average photometry mode, a localized or spotwise photometry mode and the like.

As is well recognized, the photometry used in the conventional cameras can be categorized into an average photometry and a localized (or spotwise) photometry. The average photometry can be classified into a photometry averaged over the entire image field and another which is centrally emphasized, the latter being generally employed. Such average photometry produces a passable result for the typical object and over the localized photometry in respect of the ease of use, and accordingly, this average photometry is employed in most cameras.

The localized or spotwise photometry can be effectively used for an object having a high ratio of highlight and shadow when it is desired to control the exposure in accordance with the brightness of either the highlight or the shadow. However, it requires a troublesome operation and is likely to cause a photographing operation with an improper exposure. In the past, there has been a camera offered on the market which allows the photometry of only the central region of an image field, but this makes the photographic composition difficult. Accordingly, at the present time, cameras seldom adopt such a technique.

For the reasons mentioned above, the average photometry technique an excellent technique as compared with the localized or spotwise photometry when taking a picture of an ordinary object being photographed. However, in practice, objects being photographed are not limited to those having a reduced ratio of highlight and shadow, but include a number of objects having a greater ratio of highlight and shadow such as objects in the rear light, objects on a stage and objects in a composition which is formed when viewing the outdoors through a window. In particular, it is to be noted that the chance to take a picture of an object having a higher ratio of highlight and shadow increases as a photographer makes progress in his photographing skill. If an automatic exposure camera which operates on the basis of the average photometry is used to take a picture of an object having a high ratio of highlight and shadow, the exposure is controlled in accordance with the average brightness of the object, and hence prevents the intended composition of a photographer from being achieved when it is desired to control the exposure in accordance with the brightness level of a selected region of such object.

In the prior art practice, when taking a picture of such a special object, a so-called spot meter which utilizes a very limited angle for photometry is used to determine the brightness of an object being photographed at a plurality of locations. Based on the information representing the brightness of the object thus obtained and the intended composition to impart a proper exposure to a selected region and to determine the brightness level of the shadow, exposure factors such as a diaphragm aperture and an exposure period are determined, followed by taking a picture by manual operation of the camera. Where an object is accessible as when taking a picture in a studio, an incident-light exposure meter is used to determine the brightness of an object being photographed at a plurality of desired locations in order to determine exposure factors in the similar manner as mentioned above, thus allowing a picture to be taken by manual operation. However, the use of an exposure meter which is separate from the camera to perform the localized or spotwise photometry in order to determine the exposure factors requires a troublesome procedure, an increased length of time and a complex calculation, all of which represent disadvantages.

A so-called multi-mode camera is available in the prior art. This represents a camera which allows a selection among a plurality of photographing modes including an automatic and a manual exposure mode. However, such camera does not afford a display of adequate and full photographing information within a finder since such information varies from mode to mode.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a camera of the multi-mode type having a finder within a photographing information display comprising a linear succession of a plurality of display regions is defined so that photographing information is indicated in the form of a bar by activating the display from a display region located at one end thereof to a particular display region which corresponds to the particular photographing information to be indicated and in, whenever a photographing mode is changed, the display is once entirely deactivated, followed by the activation of the display from a display region located at one end thereof to another display region which corresponds to the photographing information to be used in a new photographing mode, thus providing a positive indication that the photographing mode has been changed.

It is another object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain the values of the brightness of an object being photographed at a plurality of locations and in which such values as well as result of arithmetic operations performed on these values are displayed, with the values of the brightness being directly displayed while the result of arithmetic operations are corrected before display if an exposure correction is made.

It is a further object of the invention to provide a camera having localized or spotwise photometric means which may be used to determine the values of brightness of an object being photographed at a plurality of locations, which values are subject to an arithmetic operation to determine an exposure level, and also having a finder in which a first and a second photographing information display are defined, each comprising a linear succession of a plurality of display regions, the photometric values obtained at individual locations being indicated by separately activating corresponding display regions of the first display and the result of the arithmetic operation being indicated in the form of the bar by activating the second display from a display region located at one end thereof to another display region which corresponds to the result.

It is still another object of the invention to provide a camera having localized or spotwise photometric means which is used to determine photometric values of an object being photographed at a plurality of locations, which values are indicated within a finder on a photographing information display comprising a linear succession of a plurality of display regions, and in a photometric value which has already been determined is fixedly displayed on a corresponding display region of the display while a photometric value which is currently is determined being displayed on a corresponding display region of the display. It is a corollary object of the invention to provide a camera of the type mentioned above in which a photometric value which is being currently determined is displayed on a corresponding display region of the display in a flashing mode. It is an associated object of the invention to provide a camera of the type mentioned above in which a photometric value which is being currently determined is predominantly displayed whenever a display region which is used for the flashing display coincides with the display region in which the previous photometric value is to be fixedly displayed.

It is a stil further object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain values of the brightness of an object being photographed at a plurality of locations in a time sequence and in which an arithmetic operation is performed on these values in order to control an exposure, with these photometric values and/or results of the arithmetic operation being properly stored so that they are displayed in a photographing information display whenever such photometric values and/or results of the arithmetic operation are located within the extent of the display while a display region or display pattern representing an overexposure or an underexposure is activated if they are located outside the extent of the display, and in which whenever a new brightness value is inputted, the arithmetic operation is performed again, thereby assuring that a correct result of arithmetic operation is always available.

It is an additional object of the invention to provide a camera which permits an average photometry mode and a localized or spotwise photometry mode to be selectively used and in which when changing from the average to the spotwise photometry, the spotwise photometry mode can be established by actuating an operating member and can be reset to the average photometry mode whenever the photographing operation with the spotwise photometry is completed.

It is an yet additional object of the invention to provide a camera which permits an average photometry mode and a localized or spotwise photometry mode to be selectively used and in which the photographing mode is automatically changed from the average photometry to the spotwise photometry in response to an operation to input a spotwise photometric value.

It is yet another object of the invention to provide a camera which permits an average photometry mode and a localized or spotwise photometry mode to be selectively used and having localized or spotwise photometric means to obtain spotwise photometric values on which an arithmetic operation is applied to determine an exposure level during the localized or spotwise photometry mode, the camera also including a data erasure member to cancel the spotwise photometric values and the corresponding results of the arithmetic operation, the operation of the erasure member automatically changing the photographing mode from the localized or spotwise photometry to the average photometry mode.

It is an yet further object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain values of the brightness, from which an arithmetic mean or a weighted mean is derived to determine an exposure level during a normal spotwise photographing mode, from which the maximum value is chosen to determine another exposure level which is by a given number of exposure steps above such maximum value during a highlight referenced photographing mode, and from which the minimum value is chosen to determine a further exposure level which is by a given number of exposure steps below the minimum value during a shadow referenced photographing mode, thereby allowing the operation of the camera to be selectively changed between these three modes. It is an attendant object of the invention to provide such a camera in which the highlight- or shadow-referenced photographing mode is disabled whenever at least one or more spotwise photometric values are not inputted.

It is an yet additional object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain values of the brightness, which are then stored and in which the maximum value of the brightness is chosen as a reference to determine an exposure level which exceeds the reference by a given number of exposure steps so that an exposure period is delayed by an amount corresponding to the given number of exposure steps as compared with a shutter period which corresponds to a proper exposure for the maximum value and in which the delayed exposure period is displayed within a finder of the camera. It is an attendant object of the invention to provide such a camera in which whenever a fresh value of the brightness is inputted which exceeds the maximum value of the brightness, the fresh value is chosen as the reference to repeat the arithmetic operation to determine the shutter period.

It is also an object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain values of the brightness which are then stored and in which the minimum value is chosen as a reference to determine an exposure level which is below the reference by a given number of exposure steps so that an exposure period which is actually used may be shortened by an amount corresponding to the given number of exposure steps from an exposure period which represents a proper exposure for the minimum value and in which such shortened exposure period is also displayed within a finder of the camera. It is an attendant object of the invention to provide such a camera in which whenever a fresh value of the brightness is inputted which is below the minimum value, the fresh value is chosen as the minimum value to repeat the arithmetic operation to determine an exposure period.

It is another object of the invention to provide an automatic exposure camera including a storage member, commanding an exposure level to be stored, and in which during an initial photographing operation after a stored exposure level photographing mode has been selected by the actuation of the storage member, an exposure level which is actually used during this photographing operation and which is determined in accordance with exposure factors such as a preset diaphragm aperture, film speed or the like as well as an exposure period which is automatically controlled in accordance with the brightness of an object being photographed is stored, so that unless the stored exposure level photographing mode is reset, the given exposure level is maintained during subsequent photographing operations. It is an associated object of the invention to provide such a camera in which the stored value of the exposure level as well as a value of the exposure level which is determined in accordance with the photometric value being currently determined are displayed together within a finder of the camera. It is an attendant object of the invention to provide such a camera in which after the storage of the exposure level, a change in one of exposure factors causes the stored value of the exposure level to be varied in a corresponding manner. It is a corollary object of the invention to provide such a camera in which after the storage of the exposure level, the stored value of the exposure level is varied in response to an exposure correction so that the new exposure level represents a sum of the old exposure level and the amount of correction.

It is a further object of the invention to provide a camera having localized or spotwise photometric means which is used to obtain photometric values of an object being photographed at various locations and in which such photometric values as well as results of an arithmetic operation performed thereon are displayed as deviations from a standard exposure level which is calculated in accordance with a selected exposure period, diaphragm aperture, film speed and the like. It is a corollary object of the invention to provide such a camera in which the exposure level which is determined on the basis of results of the arithmetic operation is brought into coincidence with a fixed index representing a standard exposure level and in which the various locations on an object being photographed, the spotwise photometry of which has been made, are taken with a differential exposure level from the standard level which corresponds to the deviation from the fixed index.

It is an additional object of the invention to provide a camera of automatic exposure control type in which whenever an electronic flash is mounted on the camera, an exposure period is automatically established which is synchronized with the operation of the electronic flash and in which a fixed point index is caused to appear within a finder to indicate brightness information as a deviation from the index.

In accordance with the invention, there is provided a multi-mode camera in which whenever a photographing mode is changed, all the display regions of a photographing information display are once deactivated, followed by the activation of selected display regions, thereby providing a positive indication that the photographing mode has been changed.

Values of the brightness which are obtained by the localized or spotwise photometric means are displayed without any correction while results of an arithmetic operation performed on these values are displayed with correction. In this manner, the result of the arithmetic operation, representing an exposure level to be used, is allowed to shift through a plurality of distributed values of the brightness.

Spotwise photometric values are displayed in terms of points while the result of the arithmetic operation is displayed in the form of a bar graph, thereby facilitating a discrimination therebetween. The bar graph display assists a photographer to get the sense of the result of the arithmetic operation.

Spotwise photometric values which have already been inputted are fixedly displayed while a spotwise photometric value which is being currently determined is also displayed, thereby facilitating a recognition of the both.

In the event the spotwise photometric values and the result of the arithmetic operation lie outside the display regions of the photographing information display, a positive indication of an overexposure or underexposure is given, thereby preventing an inadvertent photographing operation with an improper exposure. Even though the overexposure or underexposure is displayed, the spotwise photometric values as well as the result of the arithmetic operation are properly stored. Hence, if the spotwise photometric values and the result of the arithmetic operation come into the display regions of the display due to a subsequent change in other exposure factors, they can be properly displayed.

The photographing mode is automatically changed from the localized or spotwise photometry mode to the average photometry mode in response to the completion of the spotwise photometry photographing operation, thus avoiding the likelihood that improper pictures may be taken as a result of a continued photographing operation in the spotwise photometry mode. The reason for resetting the operation to the average photometry mode after completion of the spotwise photometry operation is because the spotwise photometry is only rarely used and because the average photometry generally produces a passable result.

The operation is automatically changed from the average photometry to the spotwise photometry mode in response to an operation to input a spotwise photometric value. This eliminates the need for the provision of a separate member which is to be disposed on the camera to select the spotwise photometry mode, thus effectively preventing a failure in the photographing operation as a result of an inadvertent operation of or forgetting to operate such member.

The provision of a data erasure member permits the spotwise photometric values and the result of the arithmetic operation to be cancelled, facilitating the spotwise photometry to be repeated after it has once been attempted. At the same time, the actuation of the erasure member automatically changes the operation from the spotwise photometry to the average photometry mode, providing a greater convenience in use.

A selection is enabled among a normal spotwise photographing mode in which an exposure level is determined on the basis of an arithmetic mean or a weighted means of photometric values obtained with the spotwise photometric means, a highlight referenced photographing mode in which an exposure level is determined which exceeds, by a given number of exposure steps, a reference which represents the maximum one of the photometric values, and a shadow referenced photographing mode in which an exposure level is determined which is, by a given number of exposure steps, below a reference which represents the minimum one of the photometric values. Such selection enables a photographing operation which fully reflects the composition intended by a photographer. The highlight or the shadow referenced photographing mode is disabled if at least one or more photometric values from the spotwise photometry is not inputted, thus eliminating the need to reset such mode if it is inadvertently selected and thus avoiding the likelihood to miss a shutter chance.

In the highlight referenced photographing mode, an exposure period is delayed by an amount corresponding to the given number of exposure steps, as compared with an exposure period which would represent a proper exposure for the maximum value of the brightness. This permits a picture to be taken with an appropriate ratio of highlight and shadow, as referenced to an intended region of an object being photographed. The display of an actual exposure period within a finder assists a photographer in taking a picture since it is available to him beforehand. Furthermore, if a fresh value of the brightness is inputted which exceeds the maximum value of the brightness, the arithmetic operation to determine an exposure period is automatically repeated, allowing a photographer to take a picture while only paying attention to the exposure period displayed within the finder and without being troubled by a complex calculation.

In the shadow referenced photographing mode, an exposure period is shortened, by an amount corresponding to a given number of exposure steps, as compared with an exposure period which would represent a proper exposure for the minimum value of the brightness. This also permits a photographer to take a picture with an appropriate ratio of highlight and shadow as referenced to a desired region of an object being photographed. The display of an actual exposure period within the finder assists a photographer in taking a picture since it is available to him beforehand. Furthermore, if a fresh value of the brightness is inputted which is below the minimum value of the brightness, the arithmetic operation to determine an exposure period is automatically repeated, allowing a photographer to take a picture while only paying attention to an exposure period displayed within the finder and without being troubled by a complex calculation.

When a storage member is actuated, an exposure level which is stored during the initial automatic exposure is utilized during the subsequent photographing operation, permitting a plurality of frames to be exposed at the same exposure level. The stored exposure level is displayed within a finder concurrently with an exposure level which corresponds to the brightness of an object being photographed which is being currently determined, thus facilitating a comparison of the exposure levels. In the event an exposure factor other than the stored exposure level varies, the stored exposure level is also varied in accordance with the change in the exposure factor, allowing pictures to be taken always at a given exposure level. If an exposure correction is made, the stored exposure level can be changed in accordance with such correction, thus allowing the exposure level to be shifted only for those frames which require such correction.

An exposure level which is based on the spotwise photometric values and the result of the arithmetic operation is displayed as a deviation from a standard exposure level, providing a clear indication of the distribution of the brightness of an object being photographed as well as its deviation from the standard exposure level. This greatly facilitates a multiple point photometry during a manual photographing operation.

When utilizing an electronic flash, an exposure level which will be attained under natural light alone at a timing which is synchronized with the operation of the electronic flash is displayed as a deviation from the standard exposure level, allowing a photographer to recognize the degree of exposure which would be achieved with natural light alone. Hence, it is possible to determine beforehand whether or not the brightness of an object being photographed is high enough to obviate the use of an electronic flash or the degree to which a background will be over- or under-exposed when performing a daytime synchronized photographing operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a camera constructed in accordance with one embodiment of the invention;

FIG. 2 is a top plan view of the camera shown in FIG. 1;

FIG. 3 is a schematic side elevation of the optics contained within the camera of FIG. 1;

FIG. 4 is a front view of a photometric light receiver contained in the optics of FIG. 3;

FIG. 5 is a block diagram of the general arrangement of an electrical circuit contained in the camera shown in FIG. 1;

FIG. 6 is a block diagram of the internal arrangement of a microcomputer serving as a central processing unit shown in FIG. 5;

FIG. 7 is a circuit diagram of an interface utilized as a peripheral unit of the microcomputer shown in FIG. 6;

FIG. 8 is a circuit diagram of a head amplifier shown in FIG. 5;

FIG. 9 is a circuit diagram of an analog exposure information introduction circuit and a second selection circuit, both shown in FIG. 5;

FIG. 10 is a circuit diagram of an over- and underexposure decision circuit associated with an electronic flash and a first comparator, both shown in FIG. 5;

FIG. 11 is a circuit diagram of an electrical circuit of a power supply sustain circuit shown in FIG. 5;

FIG. 12 is a circuit diagram of a trigger timing control circuit shown in FIG. 5;

FIG. 13 is a circuit diagram of a battery checker circuit and a power supply reset circuit, both shown in FIG. 5;

FIG. 14 is a circuit diagram of a decision circuit associated with an electronic flash shown in FIG. 5;

FIG. 15 is a circuit diagram of a first selection circuit, an electromagnet driver circuit and an electronic flash control circuit, all shown in FIG. 5;

FIG. 16 is a circuit diagram of a timer circuit shown in FIG. 5;

FIG. 17 is a circuit diagram of a D/A converter circuit shown in FIG. 5;

FIGS. 18a and i are a series of timing charts, illustrating the waveform of various timing signals derived from the timer circuit shown in FIG. 16;

FIGS. 19A and B are plan views of display segment electrodes and back electrodes of a liquid crystal display panel which essentially comprises a photographing information display shown at 39 in FIG. 3;

FIG. 20 is a fragmentary plan view illustrating the relative relationship between the display segment electrodes and the back electrodes shown in FIGS. 19A and B;

FIG. 21 is a circuit diagram of a liquid crystal driver circuit shown in FIG. 6;

FIG. 22 is a circuit diagram of a signal synthesizer circuit shown in FIG. 21;

FIG. 23 is a circuit diagram of a level conversion circuit to which the electric circuit shown in FIG. 22 is connected;

FIG. 24 is a circuit diagram of a common signal output circuit used in the liquid crystal driver circuit shown in FIG. 6;

FIGS. 25a to m are a series of timing charts, illustrating the output waveform of various signals appearing in the liquid crystal driver circuit shown in FIGS. 21 to 24;

FIG. 26 graphically illustrates the technique employed to count an exposure period during a photographing operation in a memory mode;

FIGS. 27A to C are flowcharts schematically illustrating programs used in the microcomputer shown in FIG. 6;

FIG. 28 is a flowchart illustrating the detail of a mode determining program which is included in the flowcharts shown in FIGS. 27A to C;

FIG. 29 is a flowchart showing the detail of a program used in the flowchart of FIG. 27B and which is used during an average photometry, direct automatic photographing mode;

FIG. 30 is a flowchart which represents the detail of the flowchart shown in FIG. 27B and which is used when there is a spotwise photometric input during a spotwise photometry, automatic photographing mode;

FIG. 31 is a flowchart which represents the detail of the flowchart shown in FIG. 27B and which is used when there is no spotwise photometric input during the spotwise photometry, automatic photographing mode;

FIG. 32 is a flowchart, illustrating the detail of a program used during a highlight referenced photographing mode and a shadow referenced photographing mode, which is executed in succession to the flowchart shown in FIG. 31 which is used when there is no spotwise photometric input during the spotwise photometry, automatic photographing mode;

FIG. 33 is a flowchart which represents the detail of a program used during an electronic flash activated, automatic photographing mode and which forms part of the flowchart shown in FIG. 27A;

FIG. 34 is a flowchart showing the detail of a program used during a normal manual photographing mode, which forms part of the flowchart shown in FIG. 27C;

FIG. 35 is a flowchart, contained as part of the flowchart shown in FIG. 27C and used when there is a spotwise photometric input during the spotwise photometry, manual photographing mode;

FIG. 36 is a flowchart, contained as part of the flowchart shown in FIG. 27C and used when there is no spotwise photometric input during the spotwise photometry, manual photographing mode;

FIG. 37 is a flowchart showing the detail of a program for a highlight referenced photographing mode and a shadow referenced photographing mode, which is executed in succession to the flowchart shown in FIG. 36 which is used when there is no spotwise photometric input during the spotwise photometry, manual photographing mode;

FIG. 38 is a flowchart, contained as part of the flowchart shown in FIG. 27A and showing the detail of a program for an electronic flash activated, manual photographing mode;

FIG. 39 is a flowchart showing the detail of a program subroutine WAIT1 which is executed in the course of the flowchart shown in FIG. 33;

FIG. 40 is a flowchart showing the detail of a program subroutine WAIT2 which is executed in the course of the subroutine WAIT1 shown in FIG. 39, a subroutine WAIT3 shown in FIG. 41 and a bar display subroutine shown in FIG. 44 which will be described later;

FIG. 41 is a flowchart showing the detail of the program subroutine WAIT3 which is executed in the course of the flowcharts shown in FIGS. 31 and 36;

FIG. 42 is a flowchart showing the detail of a program subroutine to count an actual exposure time which is executed in the course of the flowchart shown in FIG. 29;

FIG. 43 is a flowchart showing the detail of a program subroutine f{(M3)} which is executed in the course of the flowcharts shown in FIGS. 28 to 38;

FIG. 44 is a flowchart showing the detail of a program subroutine to display a bar which is executed in the course of the flowcharts shown in FIGS. 28 to 38;

FIGS. 45 to 47 schematically show the manners of display produced by a photographing information display during an average photometry, direct automatic photographing mode; specifically FIG. 45 represents a bar graph of a Tv value produced within the extent of display, FIG. 46 shows a bar representation of Tv value which exceeds the extent of display, and FIG. 47 illustrates a bar representation of Tv value which is less than the lower limit of the extent of display;

FIGS. 48 to 50 schematically show the manners of display by the photographing information display during the spotwise photometry, automatic photographing mode; specifically FIG. 48 shows a bar representation of average Tv value which is within the extent of display, FIG. 49 a bar representation of average Tv value which exceeds the upper limit of the extent of display, and FIG. 50 illustrates the application of a correction;

FIGS. 51 to 54 also show the manner of display by the photographing information display when the highlight referenced photographing mode is selected during the spotwise photometry, automatic photographing mode; specifically, FIG. 51 shows a bar representation of Tv value which has once extended to a position corresponding to the maximum value of the brightness, FIG. 52 is a bar representation of Tv value which is by 21/3 Ev shifted in the negative direction from the condition shown in FIG. 51, FIG. 53 shows a bar representation of Tv value which is shifted from the condition shown in FIG. 52 by changing Sv-Av value, and FIG. 54 shows the application of a correction to the condition shown in FIG. 53;

FIGS. 55 and 56 show the manner of display by the photographing information display when a shadow referenced photographing mode is selected during the spotwise photometry, automatic photographing mode; specifically, FIG. 55 shows a bar representation of Tv value which has once retracted to a position corresponding to the minimum value of the brightness, and FIG. 56 shows a bar representation of Tv value which is shifted by 22/3 Ev in the positive direction from the condition shown in FIG. 55;

FIGS. 57 to 59 show the manner of display by the photographing information display during a direct, automatic memory photographing mode; specifically, FIG. 57 represents a memory set condition, FIG. 58 a memory hold condition, and FIG. 59 the result of applying a correction in the memory hold condition;

FIG. 60 shows the manner of display by the photographing information display during the spotwise photometry, automatic memory photographing mode;

FIGS. 61 and 62 show the manner of display by the photographing information display during the normal manual photographing mode; specifically, FIG. 61 shows a bar representation of a deviation from a standard exposure level, and FIG. 62 the result of applying a correction to the bar representation;

FIGS. 63 to 65 also show the manner of display by the photographing information display during the spotwise photometry, manual photographing mode; specifically, FIG. 63 shows a bar representation of an arithmetic mean of deviations from a standard exposure level, FIG. 64 shows the bar rerpesentation when a new spotwise photometric input is applied to the condition shown in FIG. 63, and FIG. 65 shows the result of applying a correction to the condition shown in FIG. 64;

FIG. 66 shows the manner of display by the photographing information display when a highlight referenced photographing mode is selected during the spotwise photometry, manual photographing mode;

FIG. 67 shows the manner of display by the photographing information display when a shadow referenced photographing mode is selected during the spotwise photometry, manual photographing mode;

FIGS. 68 to 72 show the manner of display by the photographing information display during the electronic flash activated, automatic photographing mode; specifically, FIG. 68 shows a point display of a deviation from a standard exposure level, FIG. 69 shows the result of applying a correction to the condition shown in FIG. 68, FIG. 70 illustrates the indication of an overexposure which is found after the photographing operation, FIG. 71 illustrates an underexposure which is found after the photographing operation, and FIG. 72 illustrates a proper exposure which is found after the photographing operation; and

FIG. 73 shows the manner of display by the photographing information display during the electronic flash activated, manual photographing mode.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

FIGS. 1 and 2 show a front view and a plan view of a camera constructed in accordance with one embodiment of the invention. A camera 10 shown represents a single lens reflex camera including a body 1, and a lens barrel 2 for a taking lens is detachably mounted centrally on the front side of the body 1. A triangular pentaprism housing 3 projects upwardly from the central portion of the top side of the body 1. As is well recognized, barrel 2 contains and carries a taking lens 4. Disposed around the periphery of the barrel 2 in a rotatable manner are a diaphragm aperture presetting ring 5, a distance presetting ring 6 and a manual exposure period presetting ring 7 in the sequence named as viewed from the front side of the barrel. Disposed on the top side of the body 1 and to the left of the pentaprism housing 3 are a plurality of operating members including a film winding lever 8, a number of film frames indicator window 9, a shutter release button 11, a self-timer operating knob 12, a memory command knob 13, a spotwise photometric data entry button 14, a highlight command button 15 and a shadow command button 16. Disposed on the top side of the body 1 and to the right of the pentaprism housing are a film rewind knob 17, a film speed presetting dial 18, a film speed indicator window 19, a mode changing knob 21, an exposure correction knob 22 and a light emission window 23 associated with a battery checker. An electronic flash mounting shoe 24 is disposed on the top surface of the pentaprism housing 3 toward the rear end thereof while a connector 25 for connection with an electronic flash, not shown, through a cord, not shown, is disposed on the front side of the body 1 toward the upper, right-hand corner thereof. In FIGS. 1 and 2