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Description  |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a camera and more particularly to an operation
device of the camera.
2. Description of the Related Art
It has been a salient feature of single-lens reflex cameras that the
interchangeable lenses of varied kinds can be selectively used as desired
by the users. The camera of this kind permits use of, for example, a
telephoto lens having a focal length of 300 mm, a wide-angle lens having a
focal length of 24 mm or a standard lens of 50 mm focal length. However,
the photographing conditions under which each interchangeable lens is to
be used are diverse. The functional arrangement of operation members of
the camera suitable for the interchangeable lens can hardly be simply and
unconditionally determined. Further, the operation member arrangement
suited to the linking of the photographers also varies. Arrangement best
suited to one person is not always suited for another. For example, in the
case of sport photography, telephoto lenses of focal length 300 mm and
above are used in most cases. An ultra-telephoto lens of 1200 mm focal
length or so is often used. Many objects to be photographed are moving
fast. Therefore, sport photography requires use of a lens of relatively
small max. open F-number (a bright lens). Such being the requirement, the
lenses to be used for sport photography are heavy. Therefore, the left
hand of the photographer is used solely for supporting the lens in case
that the camera is to be supported by hand. In such a case, the camera is
required to enable the photographer to obtain necessary exposure factors,
such as a shutter speed and an aperture value, by performing a selecting
operation by the right hand of the photographer. If the camera is fixedly
set on a tripod, the weight of the camera is carried by the tripod, so
that the left hand can be used for operation. In that case, a function of
the camera which requires an operation by the left hand and a function
which requires an operation by the right hand can be clearly separated
from each other, so that the possibility of an erroneous operation can be
lessened. Photographing with a standard or wide-angle lens is also
performed by operating the camera with two hands in general. However,
there are some cases where the camera must be operated only with the right
hand as the left hand cannot be used for the camera, like in photographing
in a place jammed with people or while riding on a bicycle, a motorcycle
or the like. Therefore, a camera arranged to be operated only in a fixed
manner hardly meets requirements for varied photographing conditions and
the diverse likings of the users.
Further, heretofore, a camera of the kind having single-shooting and
continuous-shooting modes has necessitated the following complex operation
for change-over between the single-shooting and continuous-shooting modes:
The camera is first set in a signal-shooting continuous-shooting selection
mode by operating a button. Then, a dial or an up-down switch is operated
to select either the single shooting mode or the continuous shooting mode.
After that, the camera is brought back to a photographing state either by
pushing a shutter release button down to a first stroke position thereof
or by means of a timer.
To simplify the complex mode setting operation for a speedy setting
operation, a method of turning on a switch provided for a motor drive
device of the camera to instantaneously change the single shooting mode
over to the continuous shooting mode during a photographing operation has
been disclosed in Japanese Laid-Open Patent Application No. SHO 53-125824.
While the conventional mode changing arrangement requires a period of time
which is too long to ensure timely capture of shutter chances, the method
of changing one mode over to the other by turning on the switch provided
for the motor drive device gives a poor operability. Besides, since a
switch is to be used solely for the change-over from the single shooting
to the continuous shooting, it presents a problem in finding its position
on the camera in addition to other operation switches.
SUMMARY OF THE INVENTION
It is one aspect of the invention under the present application to provide
a camera or an accessory device thereof having first and second manual
operation members in combination with a control circuit which is arranged
as follows: In a first mode, first information or a first function can be
set by the first operation member and second information or a second
function can be set by the second operation member. In a second mode, the
second information or the second function can be set by the first
operation member and the first information or the first function can be
set by the second operation member, the control circuit being arranged to
permit selection of the mode thereof.
It is another aspect of the invention to provide a camera or an accessory
device thereof having an information setting circuit which is arranged as
follows: When the setting circuit is set in a first mode, information of a
specific kind is forcedly selected by the operation of an operation
member. When the setting circuit is set in a second mode, one of
information of a plurality of kinds other than the specific kind can be
selectively set by operating the operation member, the setting circuit
being arranged to permit selection of the modes thereof.
The objects and features of this invention will become apparent from the
following description of embodiments thereof with reference to the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical sectional view taken across the middle part of a
single-lens reflex camera incorporating an embodiment of this invention.
FIG. 2 is a flow chart showing the operation of the essential parts of the
embodiment.
FIG. 3 is a circuit diagram showing an electric circuit including a
microcomputer which is arranged to control the operation of the
embodiment.
FIG. 4 is a front view of a single-lens reflex camera showing operation
members arranged according to this invention.
FIG. 5 is a top view of the single-lens reflex camera showing the operation
members arranged according to the invention.
FIG. 6 is a rear elevation of the single-lens reflex camera showing the
operation members arranged according to the invention.
FIGS. 7(a) and 7(b) are flow charts showing the operation of the
microcomputer performed prior to a shutter release operation.
FIG. 8 is a flow chart showing a swap mode setting action included in the
flow charts of FIGS. 7(a) and 7(b).
FIG. 9 is a flow chart showing a multiple exposure mode setting action
included in the flow charts of FIGS. 7(a) and 7(b).
FIG. 10 is a flow chart showing an exposure setting action included in the
flow charts of FIGS. 7(a) and 7(b).
FIG. 11 is a flow chart showing an exposure compensation setting action
included in the flow charts of FIGS. 7(a) and 7(b).
FIG. 12 is a flow chart showing a film sensitivity setting action included
in the flow charts of FIGS. 7(a) and 7(b).
FIG. 13 is a flow chart showing an automatic exposure bracketing
information setting action included in the flow charts of FIGS. 7(a) and
7(b).
FIG. 14 is a flow chart showing a photographing mode setting action
included in the flow charts of FIGS. 7(a) and 7(b). FIG. 15 is a flow
chart showing an information setting action included in the flow charts of
FIGS. 7(a) and 7(b).
FIGS. 16(a) and 16(b) are flow charts showing the operation of the
microcomputer performed after the shutter release operation.
FIG. 17 is a sectional side elevation of a camera body to which this
invention is applied.
FIG. 18 is a circuit diagram showing an electric circuit incorporated in
the camera of FIG. 17.
FIG. 19 shows the states of flags included in the flow charts.
FIGS. 20(a) and 20(b) are flow charts showing the operation of the camera
of FIG. 18.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of this invention is arranged as described below with
reference to drawings:
FIG. 1 is a sectional view showing the middle part of a camera embodying
this invention. A sub-mirror which is a second optical element is in an
uplifted state (AF distance measuring position). Referring to FIG. 1, a
camera body 40 is provided with upper and lower rail faces 41a and 41b
which are arranged to define the positions of a pressing plate 46 and the
film. A structural member 63 is formed in one unified body with a mirror
box is arranged to define the position of a focusing screen unit 48. The
focusing screen unit 48 is provided with the pentagonal prism 47 of a view
finder optical system, a focusing screen 48c, a frame body 48a and a
spring 48b which is arranged to urge upward the focusing screen 48c. A
screw 55 for a tripod is secured to the camera body 40. A back lid 45 is
arranged to keep the film shielded from light. Pressing leaf springs 46a
and 46b are arranged to push the pressing plate 46 against the rail faces.
An eyepiece frame 49 is arranged to have an eyepiece 49a secured thereto.
A light measuring lens 90 is arranged to guide light to a photometric
sensor 91. An upper cover 93 is arranged to protect the upper part of the
camera. A flash device shoe 94 is secured to the upper cover 93. The shoe
94 is provided with a synchronizing contact 94a which is arranged in a
known manner; and a signal contact 94b which is arranged for transmission
of various signals between the camera and a flash device. While only one
signal contact 94b is shown the camera is, in actuality, provided with a
plurality of signal contacts 94b. A prism 95 which is for view finder
information is arranged below the pentagonal prism 47 to show the contents
of a display made by a display element 96 in the lower part of the view
finder field when the view finder is sighted through the eyepiece frame
49. A contact 97 is arranged to permit information exchange between the
camera body and a lens unit and power supply from the camera body to the
lens unit. A spring 98 is arranged to urge the contact 97 toward the lens
unit. While only one contact 97 is shown, there are provided a plurality
of contacts 97 in the actual arrangement of the camera. A pair of fixed
pins 64a are secured to the mirror box on the right and left sides
thereof. A half-reflection fixed mirror frame 71a has a thin-film
half-reflection mirror 71b stretched on the frame to serve as a light
splitting element. The mirror 71b forms a first optical element 71. The
first optical element 71 is formed by a vapor deposition process and is
arranged to have a light flux which has passed through a photo-taking lens
system 22a to 22f split in a given ratio and supplied to the view finder
optical system (on the side of the pentagonal prism) and to a photo-taking
system (on the side of the film). The light splitting ratio is set, for
example, at 60 : 40. A keep frame body 65 is provided with a spring 66 for
urging the first optical element 71 to a given position thereof and is
arranged to be swingable on a pin 67 secured to the mirror box. A mirror
adjustment screw 68 is provided for adjusting the first optical element 71
to a position which is at a angle of about 45 degree to the optical axis
of the lenses. A fixing screw 69 is arranged to have the first optical
element 71 urged and fixed by the keep frame body 65. A lens 161 for the
AF sensor is arranged to guide a light flux coming from a second optical
element 70 to an AF sensor unit 162. A flash light adjustment lens 163 is
arranged to guide light, at the time of flash light photography, to a TTL
light adjusting sensor 164 which is arranged to measure the reflection
light of flash light. A fixed pin 64c is secured to the mirror box and is
arranged to restrict, to a given position, a sub-mirror driving plate 75
by the counterclockwise urging force of a sub-mirror driving plate
returning spring 77. Another fixed pin 64b which is also secured to the
mirror box and is arranged to restrict, to a given position during an AF
distance measuring process, the second optical element 70 by the urging
force of a sub-mirror urging spring 76 which is arranged to act between a
sub-mirror fixing plate 72 and the sub-mirror driving plate 75 to
constantly urge the sub-mirror fixing plate 72 in the clockwise direction.
A total reflection mirror 70 which is provided for an AF distance
measuring purpose as a second optical element is secured to the sub-mirror
fixing plate 72 in one unified body therewith. The sub-mirror fixing plate
72 is pivotally carried by a pin 72a to be swingable on the pin relative
to the sub-mirror driving plate 75.
A reference numeral 20 denotes a known interchangeable lens unit for AF
single-lens reflex camera. The lens unit 20 is provided with an AF-manual
change-over mechanism which is arranged between a helicoid member 23 and a
pinion gear 24 to effect change-over from automatic focusing (hereinafter
referred to AF) to manual focusing to be performed outside the camera. An
electric switch is interlocked with the AF-manual change-over mechanism.
On the side of the lens unit, there is provided a contact 25 which
corresponds to the contact 97 disposed on the side of the camera body.
These contacts 25 is arranged to permit communication of information
between the camera body and the lens unit and also power supply from the
camera body to the lens unit. While only one contact 25 is shown, the lens
unit is provided, in actuality, with a plurality of contacts 25. A bearing
26 is provided for the smooth rotation, relative to the helicoid member of
a lens carrying body 22 which has photo taking lens system 26a to 26f
fixedly attached thereto. The helicoid member 23 has a helicoid 23a and is
arranged to have the output of a motor M4 transmitted thereto via a pinion
gear 24, a reduction mechanism which is not shown and the AF-manual
change-over mechanism. A stepper motor M3 is used as an actuator for an
electromagnetic diaphragm mechanism and is arranged to drive and control
diaphragm blades 530.
FIG. 4 is a front view of the camera incorporating the embodiment of FIG. 1
and shows the arrangement of operation members as viewed from the front.
FIG. 5 shows the arrangement of operation members as viewed from above the
camera. FIG. 6 shows the arrangement of them as viewed from behind the
camera. Referring to these FIGS. 4, 5 and 6, a reference symbol RELB
denotes a shutter release button. A symbol DIAL denotes a dial which is
arranged to be used in setting a shutter speed, an aperture value, film
sensitivity information, an exposure compensation value or information on
exposure step in the case of automatic bracketing photographing (for
example, the information is obtained every 0.5 step or every one step),
etc.. For example, this is an electronic dial consisting of a conductive
pattern of two bits differing 90 degrees in phase from each other and a
brush. When the dial is turned, the pattern and the brush are scanned
relative to each other to produce a pulse.
A switch button SWM is provided for setting an aperture value while switch
swapping is not performed. In a manual exposure mode, the aperture value
can be changed b operating the above-stated dial DIAL by pushing the
aperture setting switch SWM when switch swapping is not performed.
Meanwhile, the shutter time can be changed when switch swapping is
performed.
A symbol SWMODE denotes a switch button. When the above-stated dial DIAL is
operated while pushing this switch button SWMODE, an exposure mode can be
selected from among varied modes including a program exposure mode, a Tv
priority exposure mode, an Av exposure mode and a manual exposure mode. A
symbol SWCOMP denotes a switch button. When the dial DIAL is operated
while pushing the switch button SWCOMP, an exposure compensation value can
be changed a desired.
The number of frames to be exposed can be set by operating the dial DIAL by
simultaneously pushing the switch buttons SWMODE and SWCOMP. A switch
button SWSC is arranged to permit selection of a single shooting mode, a
continuous shooting mode or a self-timer mode by operating the dial DIAL
after pushing this switch button SWSC. A switch button SWAF is arranged to
permit changing the film sensitivity information by operating the dial
DIAL after pushing the switch button SWAF together with the switch SWBC. A
switch button SWSC is arranged to permit setting of the number of steps
for automatic bracketing photographing by operating the dial DIAL after
pushing the switch button SWSC together with the switch SWAF. A switch
button SWF is arranged to permit setting and resetting of switch swapping
by pushing this switch button after pushing all the switch buttons SWMODE,
SWCOMP and SWSC.
Further, a reference symbol LCD denotes an LCD display device for
displaying the exposure mode, the photographing mode, the Tv value, the Av
value, the number of photographing frames, etc..
FIG. 3 shows by way of example the arrangement of an electric circuit using
a microcomputer COM which is arranged to control a sequence of actions.
Referring to FIG. 3, a light receiving element SPC is arranged to receive
reflection light from an object to be photographed and to supply a light
receiving signal to an operational amplifier OPl, which is of a high input
impedance and has a compression diode Dl connected to a feedback circuit
thereof. The amplifier OPl is arranged to produce via a resistor Rl
information on the luminance Bv of the object which is logarithmically
compressed. A variable resistor VRl which is connected to a constant
voltage source VGl is arranged to produce a voltage Sv corresponding to
the content of a film sensitivity information register RGIS. An
operational amplifier OP2 which has a resistor R2 connected to its
feedback circuit is arranged to compute and produce measured light
information Ev =(Bv +Sv). The measured light information Ev is supplied to
an analog-to-digital (A/D) converter ADC to be converted into an eight-bit
digital value. The digital data thus obtained is supplied to the input
ports PG0 to PG7 of the microcomputer COM.
When the above-stated dial DIAL is operated, a dial interface circuit DIF
(a counter) counts a number of clicks thus produced from the dial. The
counted value of the circuit DIF is converted into four-bit information
and is supplied to the input ports PH0 to PH3 of the microcomputer COM.
Information within the dial interface circuit DIF is reset by a pulse
signal supplied from the output port PE3 of the microcomputer COM.
When the camera is loaded with a battery BAT, a power supply Vbat is
supplied to the microcomputer COM, the decoders TVD, AVD, FRD, MDD, SCD
and the dial interface circuit DIF. When a first stroke switch SWl which
is connected to the input port PA0 of the microcomputer COM is turned on,
by the first stroke of operation on the above stated shutter release
button RELB, the potential level of an output port PF becomes high. This
causes a transistor TRbat to be turned on by an inverter INV and a
resistor R3. The voltage from the power source Vbat is then supplied as a
power supply Vcc to such circuits that consume a relatively large amount
of electric energy like the operational amplifiers OPl and OP2 provided
for the purpose of measuring light.
The input ports PAl to PAl6 of the microcomputer COM are connected to a
second stroke switch SW2 which is arranged to be turned on by a second
stroke of the operation of the release button 1; a mirror up switch SWMRUP
which is arranged to turn on when the mirror is uplifted and to turn off
when the mirror is lowered; a charge completion detecting switch SWCGE
which is arranged to turn on upon completion of a mechanical charging
process; a film switch SWFLM which is arranged to turn on every time the
process of feeding one frame portion of film comes to an end; a trailing
curtain switch SWCN2 which is arranged to turn on upon completion of the
travel of a tailing curtain; the above-stated switch SWM which is used for
setting an aperture value or a shutter time (speed) value; the
above-stated switch SWF which is used for switch swap setting or
resetting; the above-stated exposure mode setting switch SWMODE; the
exposure compensation value setting switch SWCOMP; a multiple-exposure
frame number setting switch SWME which is arranged to produce an output at
a low level when the switches SWMODE and SWCOMP are turned on; a swap
setting switch SWFUNC which produces a low level output when the switches
SWSC and SWME turn on; the switch SWAF; the photographing mode setting
switch SWSC; the switch SWBC; an automatic bracketing step number setting
switch SWABR which produces a low level output when the switches SWAF and
SWSC turn on; and a film sensitivity information setting switch SWISO
which produces a low level output when the above-stated switches SWAF and
SWBC turn on.
Output ports PE0, PE1 and PE2 of the microcomputer COM is connected to the
bases of transistors TR0, TR1 and TR2 respectively via resistors R10, R11
and R12. The transistors TR0, TR1 and TR2 are arranged to control currents
supplied to a first clamp magnet MG0, a leading curtain magnet MG1 which
is arranged to allow a leading curtain to travel and a trailing curtain
magnet MG2 which is arranged to allow the trailing curtain t travel.
Output ports PD, PC and PB are connected to the bases of transistors TR3,
TR4 and TR5 via resistors R13, R14 and R15. The transistor TR3 is arranged
to control the driving action of a charging motor MD; the transistor TR4
to control the driving action of a film rewinding motor MC; and the
transistor TR5 that of a film winding motor MB.
An output port PTVD of the microcomputer COM is arranged to supply the
content of a shutter time information register RGTv disposed within the
microcomputer or that of a film sensitivity information register RGIS to a
decoder TVD. The decoder TVD then supplies a numerical display signal
corresponding to the above-state content of the register to a display
device SEG1 which is composed of a liquid crystal, etc. and is connected
to the decoder TVD. An output port PAVD is arranged to supply to a decoder
AVD the content of each of registers disposed within the microcomputer COM
including aperture value information, automatic bracketing step
information and exposure compensation information registers RGAv, RGBR and
RGCP. The decoder AVD is arranged to produce and supply a numerical
display signal corresponding to the content of each of these registers to
a display device SEG2 which is composed of a liquid crystal, etc. and is
connected to the decoder AVD.
An output port PFRD is arranged to supply a decoder FRD with the content of
each of registers disposed within the microcomputer COM including a
photographing frame number information register RGFR and a multiple
exposure frame number information register RGME. The decoder FRD is
arranged to produce and supply a numerical display signal corresponding to
the content of each of the above-stated registers to a display device SEG3
which is composed of a liquid crystal, etc. and is connected to the
decoder FRD. An output port PISO is arranged to supply a signal of "1" or
"0" to a display device SEG4 which is composed of a liquid crystal, etc..
The display device SEG4 is arranged to display a film sensitivity setting
mode (such as "ISO") in case that the signal of "1" is received.
An output port PABR is arranged to supply a signal of "1" or "0" to a
display device SEG5 which is composed of a liquid crystal, etc.. The
display device SEG5 displays an automatic bracketing photographing mark
(such as "AEB") in case that the signal of "1" is received. An output port
PCOMP is arranged to supply a signal of "1" or "0" to a display device
SEG6 which is composed of a liquid crystal, etc.. The display device SEG6
displays an exposure compensation photographing mark (such as "+/ -") in
case that the signal of "1" is received.
An output port PME is arranged to supply a signal of "1" or "0" to a
display device SEG7 which is composed of a liquid crystal, etc.. The
display device displays a multiple exposure mark such as "ME" in case that
the signal of "1" is received.
An output port PMODE is arranged to supply to a decoder MDD the content of
an exposure mode display information register RGMD disposed within the
microcomputer COM. The decoder MDD supplies an exposure mode display
signal corresponding to the content to a display device SEG8. The display
device SEG8 then displays, for example "M", "Tv", "Av", "P" or the like.
An output port PSC is arranged to supply a decoder SCD with the content of
a photographing mode display information register RGSC disposed within the
microcomputer COM. The decoder SCD then produces a signal for a
photographing mode display corresponding to the content of the register
RGSC. This signal is supplied to a display device SEG9 which is composed
of a liquid crystal, etc. and is connected to the decoder SCD. the display
device SEG9 then makes a display, for example, such a mark as "S", "C"or "
".
An output port PFUNC is arranged to supply a signal of "1" or "0" to a
display device SEG10 which is composed of a liquid crystal, etc. The
display device SEG10 then displays, a swap switch setting mode, such as
"FUNC", when the signal of "1" is received.
an output port PSET is arranged to supply a signal of "1" or "0" to a
display device SEG11 which is composed of a liquid crystal, etc.. The
display device SEG11 then displays a swap mode, for example, as "SET" in
case that the signal of "1" is received.
an output port PAV is arranged to supply the content of an aperture value
information register RGAv disposed within the microcomputer COM to an
aperture control driving circuit DAV. The aperture control driving circuit
DAV then produces information on an actual aperture value by converting
the content of the register. The information is then supplied to a driving
actuator CAV which is, for example, a stepper motor or the like. This
drives the actuator for adequate aperture control.
The microcomputer COM is arranged to operate as described below with
reference to FIGS. 7(a) and 7(b) to 16(a) and 16(b);
Referring to the flow charts of FIGS. 7(a) and 7(b), with the camera loaded
with a battery BAT, all flags within the microcomputer COM are completely
cleared by generation of a power supply Vbat. The flow of operation of the
microcomputer begins at "START". Sept 1: If the photographer pushes the
release button RELB only to the first stroke position thereof, a signal
indicating the on-state of the first stroke switch SWl is supplied to the
input port PAO. Then, the flow comes to a step 2. Step 2: The signal of
"1" is produced from the output port PF to turn on the transistor TRbat.
As a result, the power supply Vcc is supplied to each applicable part. The
light measuring timer is started. The light measuring timer is provided
for the purpose of allowing the power supply Vcc to be continuously
supplied for a given period of time after the first stroke switch SWl is
turned off. The arrangement of the timer allows the photographer to see
the light measuring state of the camera for the given period of time after
his or her hand is detached from the release button RELB. This enables the
photographer to change the setting information while checking the display
by operating the dial DIAL. This arrangement can be easily made by means
of the hardware timer disposed within the microcomputer COM.
Step 3: Measured light information Ev which has been converted into an
eight-bit digital value by the A/D converter ADC is stored by the register
RGEv disposed within the microcomputer. Step 4: The content of the
register RGIS which stores film information is added to the content of the
register RGEv. A sum thus obtained is stored at the register RGEv. Step 5:
The content of the register RGMD which stores exposure mode data is read
out and checked to see if it indicates a program mode. The register RGMD
is arranged to store such data as "0", "1", "2", "3", etc. according to
such varied exposure modes as the program mode, the Tv priority mode, the
Av priority mode, the manual mode, etc.. If the current content of the
register RGMD is found to be "0", thus indicating the program mode, for
example, the flow proceeds to a step 6.
Step 6: A programmed computing operation is performed on the basis of the
max. open aperture information, the measured light information Ev, etc.
according to a given program curve. By this, an aperture value, a shutter
speed, etc. are obtained. The computed values thus obtained are stored at
the aperture information register RGAV and the shutter speed information
register RGTV. Since this program computation is not directly related to
this invention, the details of it is omitted from the description. Step 7:
One half of the content of the register RGBR storing the automatic
bracketing exposure step number information is stored respectively at the
aperture bracket step number register RGBT. Step 8: A flag FSWAP which is
arranged to indicate whether or not a swap switch mode is set is checked.
If the swap switch mode is not set, the flow proceeds to a step 9. Step 9:
The output of the output port PSET is set at "0" to put out a swap mode
display. Step 10: A flag FME which is arranged to show whether or not the
multiple exposure mode is set is checked. If the flag does not show the
multiple exposure mode, the flow proceeds to a step 11.
Step 11: The content of the register RGCP which stores the exposure
compensation information is read out and checked to see if the exposure
compensation mode is set. If the content of the register RGCP is 0, thus
indicating that the exposure compensation mode is not set, the flow
proceeds to a step 12. Step 12: The output of the output port PCOMP is set
at 0 to put out an exposure compensation mode display. Step 13: A flag
FABR which is arranged to show whether or not the automatic bracketing
mode is set is checked. If not, the flow proceeds to a step 14. Step 14:
The flag FsFC which is arranged to show that a swap switch is in the
process of being set, a flag FsAB which is arranged to show that automatic
bracketing is in the process of being set, a flag FsIS which is arranged
to show that a film sensitivity value is in the process of being set and a
flag FsSC which is arranged to show that a photographing mode is in the
process of being set are cleared. Step 15: The content of the aperture
information register RGAv is produced from the output port PAVD, that of
the shutter informatio register RGTv from the output port PTVD, that of
the photographing frame number information register RGFR from the output
port PFRD, that of the exposure mode information register RGMD from the
output port PMODE and that of the photographing mode information register
RGSC from the output port PSC respectively. As a result, a setting value
of aperture is displayed by the display device SEG2, that of shutter time
(or speed) by the display device SEG1, that of the number of photographing
frames by the display device SEG3, the selected exposure mode by the
display device SEG8 and the selected photographing mode by the display
device SEG9 respectively.
Step 16: A check is made to see if a signal indicative of an on-state of
the second stroke switch SW2 is received at the input port PAl with the
release button RELB operated to the second stroke position thereof. If
not, the flow of operation comes back to the start. Then, so long as the
signal indicating the on-state of the first stroke switch SW1 is received,
this routine is continuously executed to obtain the setting information on
the luminance of the object, film sensitivity, the number of photographing
frames, the exposure mode and the photographing mode; and to obtain and
display the results of a computing operation on the setting information.
If the camera is set in the shutter priority mode, the flow of operation
proceeds in the sequence of Step 5 - Step 17 - Step 18.
Step 18: The content of the shutter information register RGTv which stores
information set by operating the dial DIAL is substracted from that of the
register RGEv and the result of the subtraction is stored at the aperture
information register RGAv. The contents of all the registers of the
microcomputer COM are arranged to be retained as long as the camera is
loaded with the battery BAT. Further, when the battery BAT is initially
loaded, information on a value expected to be frequently used, such as
1/125 sec is arranged to be initially set.
Step 19: The content of the register RGBR which stores information on the
exposure step number of automatic bracketing is stored at the aperture
bracketing step number register RGBA. The content of the shutter
bracketing step number register RGBT is set at zero (0).
After this, the sequence of operation in the shutter speed priority mode
progresses in the same manner as in the case of the program exposure mode
described. The shutter speed value set at the step 15 is displayed by the
display device SEG1 and the computed aperture value by the display device
SEG2 respectively.
Further, if the camera is set in the aperture priority mode, the flow of
operation proceeds in the sequence of Step 5 - Step 17 - Step 20 - Step
21.
Step 21: The content of the register RGAv which stores information set by
operating the dial DIAL and the aperture value setting switch SWM is
subtracted from that of the register RGEv. The result of this is stored at
the shutter information register RGTv. In case that the battery BAT is
loaded for the first time, information on a value expected to be
frequently used, such as F 5.6, is initially set. Step 22: The content of
the bracketing step number register RGBR which stores information on the
step number of automatic bracketing exposure is stored at the shutter
bracketing step number register RGBT. Meanwhile, the content of the
aperture bracketing step number register RGBA is set at zero.
After that, the sequence of operation in the aperture priority mode
progresses in the same manner as in the case of the shutter priority mode.
The aperture value set at the step 15 is displayed by the display device
SEG2 and the computed shutter speed (time) value by the display device
SEGl respectively.
If the camera is set in the manual exposure mode, the flow of operation
proceeds in the sequence of Step 17 - Step 20 - Step 23. Step 23: The
content of the register RGTM which stores information on a shutter time
value set by operating the dial DIAL is stored at the shutter information
register RGTv. This step is provided for the purpose of retaining the
information set by the dial operation, because: The content of the
register RGTv varies at every photographing shot in case that automatic
bracketing photographing mode is set in the manual exposure mode. The
details of this will be described later. After this, the flow proceeds in
the same sequence as in the case of the aperture priority mode. The
aperture value set at the step 15 is displayed by the display device SEG2
and the set shutter value by the display device SEGl respectively.
Next, when information is set by the dial operation while the light
measuring (photometric) timer is in action, the microcomputer operates as
follows: If the (first stroke) pushing operation on the release button 1
comes to a stop during the sequence of actions described above, a signal
indicative of the off-state of the first stroke switch SWl is received.
This causes the flow of program to comes from the step 1 to a step 24.
Step 24: The swap setting switch SWFUNC is checked. If the switch SWl has
been just turned off and no switches have been operated as yet, the flow
proceeds to a step 25. Step 25: The multiple exposure setting switch SWME
is checked. The flow proceeds to a step 26 like in the case of the step
24. Step 26: The exposure mode setting switch SWMODE is checked. The flow
likewise proceeds to a step 27. Step 27: The exposure compensation switch
SWCOMP is checked. The flow likewise proceeds to a step 28. Step 28: The
film sensitivity setting switch SWISO is checked. The flow likewise
proceeds to a step 29. Step 29: A check is made for the position of the
automatic bracketing switch SWABR. The flow then likewise proceeds to a
step 30. Step 30: A check is made for the position of the photographing
mode setting switch SWSC. The flow likewise proceeds to a step 31. Step
31: A check is made for the state of the flag FsFC which is arranged to
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