JPH02203327A - Camera system - Google Patents

Abstract

PURPOSE:To readily perform photographing operation by discriminating whether a photographing optical system mounted on a camera main body side is an automatic diaphragm type controlled by the camera main body or not and automatically regulating selective exposure control modes if the photographing optical system is a non-automatic diaphragm type. CONSTITUTION:A selecting means which alternatively selects an exposure controlling mode among plural exposure controlling modes, a discriminating means which discriminates whether the mounted photographing optical system is the automatic diaphragm type controlled by the camera main body or not, and a regulating means are provided. The regulating means performs regulations so that the number of the exposure control modes which can be selected by the selecting means when it is discriminated that the photographing optical system in the non-diaphragm type is mounted by the discriminating means is below the number of the exposure control modes when it is discriminated that the photographing optical system in the automatic diaphragm type is mounted. Thus photographing is constantly performed under proper exposure control.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention changes the number of selectable exposure control modes depending on whether or not an automatic aperture type photographing optical system is attached to the camera body. Regarding the camera system.

[Conventional technology]

With interchangeable lens cameras, in addition to normal shooting in which the interchangeable lens is attached directly to the camera body, the interchangeable lens can also be attached to the camera body via a bellows, reverse adapter, intermediate ring, etc. There are various ways to use it, including using it as a so-called pinhole camera without attaching it.

Furthermore, it is common practice for the above-mentioned interchangeable lens, bellows, reverse adapter, intermediate ring, and other photographic optical systems to be equipped with a mechanism for automatically determining the aperture diameter of the interchangeable lens under control from the camera body. There is.

[Problem to be solved by the invention]

If a photographic optical system with such an automatic aperture mechanism is attached to the camera body, wide-open metering is possible, in which the aperture is opened to measure the light, and all of the various exposure control modes that can be controlled by the camera body can be executed. be able to.

However, if a photographic optical system that is not equipped with the above-mentioned automatic aperture mechanism is attached to the camera body, aperture metering will be performed, so all exposure control modes provided on the camera body side will not be properly adjusted. It doesn't necessarily mean it will be executed.

Therefore, the photographer must constantly check whether the photographic optical system attached to the camera body is equipped with an automatic aperture mechanism, which makes photographing operations complicated and inconvenient.

[Means to solve the problem]

In order to solve the above problems, this invention determines whether the photographic optical system attached to the camera body is an automatic aperture type controlled by the camera body or not, and controls the selectable exposure control mode. The camera is equipped with multiple photographic optical systems that are selectively attached to the camera body, including an automatic aperture photographing optical system that automatically determines the aperture diameter to a desired value under control from the camera body. In a camera system in which the camera body selectively operates in multiple exposure control modes, including a mode in which the aperture diameter of the photographic optical system is automatically determined by control from the camera body, the multiple exposure control modes described above can be selectively operated. a selection means for selecting; a determining means for determining whether the photographic optical system installed is of an automatic aperture type controlled by the camera body; and a determining means for determining whether the photographic optical system of the non-automatic aperture type is installed. When it is determined that the above-mentioned selection means is used, the number of exposure control modes that can be selected by the selection means is limited to a smaller number than the number of exposure control modes that are used when it is determined that an automatic aperture type photographing optical system is attached. It is characterized by having the following.

[For production]

It is determined whether the photographing optical system mounted on the camera body side is an automatic aperture type controlled by the camera body, and if it is a non-automatic aperture type, selectable exposure control modes are automatically limited.

〔Example〕

Fig. 1 is a circuit diagram of the camera body side showing an embodiment of the present invention, Fig. 2 is a circuit diagram of the inside of the lens adapter attached to the camera body, and Fig. 3 is a circuit diagram of the lens adapter attached to the camera body. It is a circuit diagram inside a lens. In Figure 1, BA
is a power supply battery, and Sl is a photometry switch that is closed in conjunction with a photometry button (not shown). This photometry switch S1
When the transistor BT1 is closed, the transistor BT1 becomes conductive, and power is supplied from the power supply battery BA to the power-on reset circuit 1, an exposure control section (FIG. 5), etc., which will be described later, via the power supply line +V. Power-on reset circuit 1 connects power line +V
The power-on reset signal FOR is activated by starting power supply from
This signal FOR outputs flip-flop FF1.
, registers REG2-REG,3, D flip-flop DF□, and frequency divider D11. Also,
The counter, flip-flop, register, decoder, etc. shown in the figure are constantly supplied with power from the power supply battery BA via the power supply line +E.

Furthermore, when the photometric switch S1 is closed, the inverter IN1
The output of D flip-flop DF becomes "High" and at the rising edge of the next clock pulse CP from oscillator PG.
By the Q output of 1 becoming “High”.

The gate of AND circuit AN is opened and AND circuit AN□
A clock pulse CP is now sent to the frequency divider DI□. At the same time, this "High" signal is also given to the one-shot circuit O8l, and the one-shot circuit oSl
A “High” pulse for a predetermined period of time is output from the OR circuit O.
It is sent to clip flop FF1 via R1. This pulse sets the clip flop FF1 and makes the Q output "High".

Further, this "High" signal is sent to the inside of the camera body and to the accessories, and serves as a start signal 5tart for starting the reading operation.

By this start signal S start t, the AND circuit AN
2 is opened, the reset state of the counters Co, . . . Co□ is released, and the decoder DE! becomes ready for output. Counter C01 is AND circuit AN2
Oscillator PG or clock pulse CP sent via
The decoder DE outputs one of the output terminals TBo to TB7 according to the output of the counter CO□.
Table 1 shows the relationship between the input and output of this decoder DE1.

Table 1 Terminals JA□, JA2 of the lens adapter shown in Figure 2. J
A3゜JA41JA5 are terminals JB1 on the camera body side respectively.
．． JB2゜JB3. JB4. Connected to JB5, JA,
is the terminal that receives the power supply line +E from the camera body,
JA2 is the terminal to which the clock pulse CP is input from the camera body, and JA3 is the read start signal 5t from the camera body.
The terminal to which art is input, JA4 is a common body ground terminal, and JA5 is a terminal for outputting data from the lens adapter to the camera body. Note that the terminals JL-JL5 of the interchangeable lens in Figure 3 are the terminals J of the lens adapter in Figure 2.
Similar to A□ to JA5, these are terminals connected to the camera body. From terminal JB3 on the camera body to terminal JA3 or JL
When the reading start signal 5tart is input through 3, counters CO3 and C04D flip 7 in FIG.
The reset state of the 0-tube DF3 is released, and the decoder DE
3 and the output of ROM ROl becomes possible. Also,
At the same time, this signal 5tart is also applied to the one-shot circuit O84, and the 7-rip, 70-tube FF2, FF3 are reset by the pulse from the one-shot circuit O84.

Similarly, in FIG. 3, counters co, , co,
,co,,D flip-flop DF5. The reset state of DF6 is released, and decoder DE4 and ROM RO2
can be output. Furthermore, the pulse from the one-shot circuit O85 causes 7 rip, 70 knob FF4, FF5, and FF.
6 is reset. Counter C03 and decoder DE3 in Figure 2 and counter CO, decoder DE4 in Figure 3
have the same configuration as the counter CO1° decoder DE1 in FIG. 1, and the decoders DE3 . Pulses are output from the respective output terminals TAo-TA, , TLo-TL of DE4 at the same timing to the output terminals TBo-TB7 of the decoder DE1, and the output terminals TAo-TA, TLo-TL of DE4 output pulses at the same timing, respectively, to the camera body and accessories.
It is synchronized with the other side.

＼ ＼ Table Table 2-1.2-2.2-3 shows the relationship between the address and the contents of various types of data in the ROM where various data of accessories are stored. 1 Table 3 shows the coded It shows the relationship between data and the content indicated by the data. In the following operation description, Tables 2-1, 2-2.2-3. The explanation will be based on Table 3. In FIG. 2, when the read start signal 5tart is output, the flip-flop FF2 is reset via the one-shot O84, so even if the D-clip flop DF3 is released from the reset state, its Q output remains high. Similarly, in FIG. 3, the Q output of the D flip-flop DF5 remains "Low" and the switch circuit AS2 remains non-conductive. In this case, data from the lens adapter can be transmitted to the camera body.

First, the output of counter CO4 becomes "01" by the pulse of TAL from decoder Ds3, "0000001" is given as the address of ROM ROl, and the address where the lens adapter check code 11100" is stored is specified. , from ROM ROl.

Data "11100" is output. Then, the flip-flop FF3 is connected to the terminal T by the AND circuit AN23.
Clock pulse C output while A1 is “High”
It is set at the falling edge of P, and reset by the falling edge of the clock pulse CP outputted by the AND circuit AN22 while the terminal TA2 is "High." Therefore, the Q output of flip-flop FF3 is "High" at terminal TA1.
From the falling edge of clock pulse CP during
becomes “High” only until the falling edge of the clock pulse CP during “High”, and the rising edge of the clock pulse CP during this period, that is, the terminal TA2 becomes “ili gh”.
”, ROM RO is stored in shift register SR2.
Data from l is captured in parallel.

Thereafter, in synchronization with the rising edge of the clock pulse CP applied to the terminal CL, the above data is sequentially output in series from the most significant bit as described below, and the data is output from the switch circuit As to the terminal J.
A5. The signal is taken into the shift register SR shown in FIG. 1 via JB5. Here, the shift register SR is sequentially connected to the terminal JB5 in synchronization with the falling edge of the clock pulse (CP).
The data is taken in one bit at a time. Since the data sent from the lens adapter is 5 bits, the first bit of the data sent at the rising edge of TA3 is Ta.
TA4.2 is read into the shift register SR1 on the camera body side at the falling timing of the clock pulse CP during "High", and thereafter TA4. TA, ,TA6. One bit is sent at each timing of TA. In this way, one data read is completed at the falling edge of the clock pulse while Ta7 is "High", and the primary terminal T
At the timing of the rise of Bo, the output data of the shift register SR is latched in parallel to the register REG1.

The decoder DE2 on the camera body side has the input and output relationships shown in Table 4.

Table 4 Here, the counter CO2 whose output is given as an input to the decoder DE2 counts each time the terminal TB rises. First, when the first data, that is, the check data, is latched into the register REG at the timing when the terminal TBo rises, the terminal d of the decoder DE2. is “High”. Therefore, terminal T
The rising signal of B is applied to the latch terminal of register REG2 via AND circuit AN3, and the data from register REG is latched into register REG2. The output of this register REG2 is judged by the AND circuit AN ts to determine whether it is 11100', and when the lens adapter is attached and the output is -11100', the AND circuit AN
The output of ts is "High", and when the lens adapter is not attached, it is "Low". The output of this AND circuit AN ts is given to a display section (not shown) that displays whether or not a lens adapter is attached.

In Fig. 2, at the next rising edge of terminal TA, the counter CO
The output of 4 becomes "acoustic music", and ROM ROl is.

-ooooooio” address is specified. Then R
OMRO□ outputs data indicating the type of lens adapter, as shown in Table 2-1. This data is shown in Table 3
If the automatic diaphragm interlocking type bellows is used, “00001” is shown.
” If it is an automatic aperture interlocking type reverse adapter, “00”
It is predefined as 010''.

This data is also processed in the same way as above, so that the terminal TBo is "Hi".
gh'', register REG on the camera body.
is latched to 1, and at this time the output of counter CO□ is “0”.
010'' and as shown in Table 4, the terminal d1 of the decoder DE2 is ``High'', so the register REG
3, data from register REG1 is latched.

Furthermore, when the output of the counter CO4 reaches 10", a "High" pulse is output from the one-shot circuit O83, and the flip-flop FF2 is set. Then, when the primary terminal TAo rises to High' ( At this time, the transmission of the lens adapter type data has been completed), and the D flip-flop DF3 sets the D input (that is, the Q output of the flip 70-tube FF2) to "Low" and makes the switch circuit AS□ non-conductive. To prevent data from being sent from a lens adapter.

Similar to the counter CO4 in FIG. 2', the counter C06 in FIG. 3 also counts the rising edge of the terminal TL, and when the count output reaches 010'', the output of the AND circuit AN25 goes ``High'' and the one-shot circuit A "High" pulse is output from O86, and the flip-flop FF4 is set.Then, similarly to the D-clip-flop DF3 in FIG.
The Q output of becomes “High” at the rising edge of terminal TLo,
The switch circuit AS2 becomes conductive and data can be sent from the interchangeable lens. Then, at the next rising edge of the terminal TL, the output of the counter CO6 becomes "011". The 3-bit output from this counter CO6 is given to the lower 3 bits of the β1 input of the multiplexer MP2. At this time, the Q output of the D flip-flop DF6 is still "Low", so the multiplexer MP2 outputs data "0000011" from β□, and this data becomes the address signal of ROM RO□.Then, Table 2-
As shown in IK, check data "11100" is output from the ROM RO□, and thereafter read into the register REG4 in FIG. 1 in the same manner as described above. In addition, the third
AND circuit AN2B + AN29) OR circuit O in the figure
R4° flip-flop FF6. shift register SR
3 are the circuits AN23.3 of FIG. 2, respectively. AN24. OR
3. It is a circuit similar to FF3°SR2.

The data read into the register REG is determined by the AND circuit AN ts whether it is "11100" or not. If it is determined that it is not "11100", it means that the interchangeable lens is not attached, so the AND circuit AN
The output of ts becomes High'', the gate of AN ty is opened, and the pulse from terminal TB3 becomes the read end signal e.
Output as ndl. The following terminal TL□ is “High”
”, the output of counter CO6 is “100” “
101", "110", "111", and from multiplexer MP2 11000100", "0000"
101", -0000110", -000011
1” address data is output sequentially.Here, 1 Table 2
-1, the above address of ROM RO2 contains the maximum aperture value Av (1, minimum aperture value Avm) of the interchangeable lens.
Data of ax, wide side focal length, and Te1e side focal length are stored. To explain specifically using Table 3, the aperture value data is a general aperture value that increases at a pitch of 0.5 Ev from Fl, 2, that is, Fl, 2 to F3.
Up to 2 is 100000'~=1001 de, and the above 0.
The aperture values F1.8 to F6.9, which do not correspond to the aperture value of 5 Ev pitch and often exist as the open aperture value of a lens, are defined as "10100" to "11110", respectively. In addition, the focal length data is classified into 8w or less to 1000w or more as shown in Table 3, and data from °ooooo" to "11110" is defined. , the focal length data is stored in the address -0000110' for a zoom lens.
The minimum focal length data for each side is stored. on the other hand.

“0000110” for fixed focal length interchangeable lenses
The above focal length data is stored in the address “00” as is.
Data "11111" indicating that the focal length is fixed is stored at the address "00111".Therefore, data "11111" indicating that the focal length is fixed is stored.

The above address data “00” from multiplexer MP2
By sequentially outputting “00100” to “0000111”,
The data of the open aperture value, minimum aperture value, wide side focal length, and Te16 side focal length of the interchangeable lens is stored in register REG5. on the camera body side. REG6. REG, RE
The data is sequentially read into G8. Also, the AND circuit AN+s determines whether the output of the register REG8 into which the data on the Te1e side is read is "11111", and if the focal length of the interchangeable lens is fixed, the output of the AND circuit AN ts is becomes “High”.And,
The D clip flop DF2 takes in the D input (ie, the output of the AND circuit AN ts) at the rising edge of the terminal TB2 of the decoder DE1 when the terminal d6 of the decoder DE2 is "High".

In FIG. 3, when the output of the counter CO6 becomes 1111'', the output of the AND circuit AN26 rises to ``High'', and a ``High'' pulse is output from the one-shot circuit O87. is set, and at the next rising edge of terminal TLo, the Q output of D clip flop DF becomes "High".This opens the gate of AND circuit AN27 so that the pulse from terminal TL1 is input to counter C07. and β2 from multiplexer MP2.
Human data will be output. When the Q output of the D-clip flop DF6 becomes "High" and the next pulse from the terminal TL1 is input to the counter CO7, the output of the counter co7 becomes "001", and from the multiplexer MP1, from the block 10 to α1. The input data will be output. This block 10 outputs data corresponding to the amount of deviation (movement amount) of the distance ring as a distance setting member of the interchangeable lens from the position (2). This data is designed to output 4-pit data starting with "oooo" no matter what kind of interchangeable lens it is.This data is sent to the lower 4 bits of input β2 of multiplexer MP2, and the upper 3 bits are also output. Since the output of counter C07 is given to .

Multiplex? MP2 to bar 0010000---0
Address data of one of 011111- is output and inputted to ROM RO□. ROM RO□
As illustrated in Table 2-1, the area from addresses -0010000' to "0011111" stores data on the photographing distance according to the amount of deviation from the ω position of the distance setting section of the interchangeable lens. Therefore, this data is read into the register REG of the camera body.

Next, when the output of the counter Co7 becomes "010", the multiplexer MP outputs the data input from the block 11 to α2. This block 11 outputs data corresponding to the number of aperture steps from the open aperture position of the aperture ring as an aperture setting member of the interchangeable lens. This data is also output as 4-bit data starting with "oooo" for any interchangeable lens. Note that if it is an interchangeable lens with a fixed aperture (for example, a reflective telephoto lens), only the data of "oooo" will be output. From the multiplexer MP2, -0100000" will be output.
One of the data from -0101111- is output and this data is input to ROMRO2. ROMR
Address of O□-0100000"~"0101111
As illustrated in Table 2-1, the ``area'' stores data on the aperture value corresponding to the number of stops from the open aperture value of the aperture ring of the interchangeable lens.
The set aperture value data outputted from 2 is read into the register REG1o of the camera body.

In Fig. 1, when the set aperture value data is read into registers REG and o, if the Q output of D flip-flop DF2 is "High", that is, the attached interchangeable lens is a fixed focal length lens. If it is determined that this is the case, the gate of the AND circuit AN2° is opened, a pulse from the terminal TB2 is outputted as the read end signal end2, and the read operation is completed. This is because all the data that is subsequently read is related to the zoom lens, so there is no need to read it in the case of a lens with a fixed focal length.

In FIG. 3, when the output of counter C07 becomes "011", multiplexer MP1 outputs block 1 to α3.
Two types of data are output. This block 12 outputs the amount of deviation from the wide side focal length position of the zoom ring as the focal length setting member of the zoom lens.
4-bit data starting from "0000" is output to blocks 10 and 11. multiplexer mp
From 2, β2 to 0110000"~-0111111
” is output, and this data is sent to RO.
3, ROM RO□ address input to MRO2
In the area from 0110000'' to @0111111'', data on the focal length setting corresponding to the front position is stored, and this data is output from the ROM RO□ and read into the register REG1□ on the camera body side.

Next, when the output of the counter C07 becomes "100", the data from α3 is also output from the multiplexer MP, and the data from -1000000' to -100 is outputted to the ROMRO2.
One data of 1111' is input. this"
ROM RO of 1oooooo6″~”1001111”
As illustrated in Table 2-2, the address area □ stores data △Av of the amount of change in aperture value due to changes in the focal length of the zoom lens, and this data is stored in the RO
Output from MRO2 and register REG of camera body
, loaded into □.

Next, when the output of counter CO7 becomes "101", multiplexer MP outputs the data from block 12, which is also from α3, and ROMRO2 receives "101".
One piece of data from 10000" to 1011111' is input. In this ROM RO2 area, the set focal length f of the zoom lens is the shortest focal length f on the wide side.
Also stored is data indicating how much of the range (what percentage from fmin to the long focal length side) min is within the range up to the longest focal length f max on the Te1e side. To explain this data in more detail, this data is 1 (-00001”) if the value of is between 0 and 19%.
area, 2 ("oooio") if it is 20-39%
) area, 3 (“00100
”), if it is 60-79% then 4 (“oiooo
o'') area, 5 (-1
This data indicates that the area is 0000'').

At the same time as the data indicating the above area is read into the register REG13 on the camera body side shown in FIG.
A read end signal end3 is output from N2□, and a read end signal end is output from the OR circuit OR3.

This end signal end is sent to the clip 70 block FF via the OR circuit OR2, and this flip-flop F
F, or is reset. Therefore, reading start terminal 5
tart becomes "LOW" and counter Co1. C.O.
2. The D flip-flop DF2 is in a reset state, and the decoder DE is also in a state in which it is unable to output a timing signal. Similarly, counters CO3, CO4 and D flip-flop DF3 in FIG. 2 are reset, and decoder DE3. ROM ROl becomes unable to output. Furthermore, the counter co5. of FIG. co6. co7. D71
J 7'-70 7' DF5゜DF6 enters the reset state and decoder DE4. ROMRO2 becomes unable to output. Do as above.

The reading operation is now complete.

In Figure 1, when reading is completed, the photometry switch S
1 remains closed, the Q output of the D flip-flop DF1 remains "High", so the clock pulse C is passed through the AND circuit AN1.
P continues to be input to the frequency divider D11, and a clock pulse of, for example, 4 Hz is output from the frequency divider D11. This 4
One-shot circuit O8 starts at the rising edge of the Hz clock pulse.
2 outputs a “High” pulse, and the OR circuit O
It is input to the flip-flop FF1 via R1 and set again, the Q output becomes "High" and a read start signal is output. Therefore, if the photometry switch S1 remains closed, data from the lens adapter and interchangeable lens will be read repeatedly at a cycle of 4 Hz.

Here, the specific structure of the setting members shown by blocks 10, 11, and 12 in FIG. 3 will be explained below based on FIG. 4, taking an aperture ring as an aperture setting member as an example.

FIG. 4 is a circuit diagram showing the configuration of the setting member.

In the figure, the sliding member VT is set at a position corresponding to the setting position of the aperture ring 13 (one of the positions from ■ to [phase]) by mechanically licking the aperture ring 13 on the lens side. The conduction pattern CT is grounded, and the conduction patterns PAo-PA3 are connected to the power supply path + through resistors, respectively.
Connected to E. Therefore, when the contact piece of the sliding member VT comes into contact with any of the conductive patterns PAo to PA3, the conductive pattern PA.

~PA3 is selectively short-circuited to the conductive pattern CT.

The outputs of the inverters 1N2O to 1N23 connected to the contacting conductive pattern PA6"PA3 selectively become ``High''. When not, the outputs of inverters 1N2O to 1N23 are both “Low”.
"become.

The output of the inverter IN23 is connected to the output terminal d3 and one input of the exclusive or EO□. The output of the inverter ■N2□ is connected to the other input of the exclusive OR EO□, and the output of the exclusive OR EO2 is connected to the output terminal d2 and one input of the exclusive OR EO1. The output of the inverter IN2□ is connected to the other input of the exclusive OR EO, and the output of the exclusive OR EO is connected to the output terminal d1 and one input of the exclusive OR EO. And inverter ■N2
The output of o is connected to the other input of exclusive or EOo, and the output of exclusive or EOo is output terminal d. It is connected to the.

The conduction patterns PAo-PA3 are gray codes, and Table 5 shows the relationship between the outputs of the input terminals do%d3 of the inverters IN2°--N23 at each position 1-[phase] based on this code. Table 6 also shows the number of narrowing stages at each position.

Table 6 Below, the relationship between the set aperture value and the set positions of the sliding member VT will be explained. For lenses with Fl, 2 to F 16, the aperture ring should be F 1.2 (Av =
0.5), the sliding member VT is at the position ■, and the terminals d3 to do output data oooo'' with the number of stages of diaphragm being 0, and F 1.4 (Av
== If set to 1), the sliding member vT is at the position ■, and data "0001" for the number of narrowing stages 05 is output from the terminals d3 to do. Similarly, F
If set to 13 (Av = 7.5), terminal d3~
Data 1110'' indicating the number of refinement stages is 7 is output from do, and when F 16 (Av = 8) is set, data "1111" indicating the number of refinement stages is 7.5 is output.

FIG. 5 is a block diagram showing an exposure control section that performs exposure control based on data read into the camera body side of FIG. 1. This figure 5 shows countermeasures when an interchangeable lens is not attached or a lens adapter without an automatic aperture mechanism is attached, and how the effective aperture of the lens changes by attaching the lens adapter.
Countermeasures are being taken when the aperture becomes smaller than the set aperture value.

The photometry circuit inputs a photodetector PD that performs so-called TTL photometry that measures the light from a subject that has passed through a lens, and its output is converted from AD to AD by an AD conversion circuit 2. This output is based on the subject brightness as Bv, the maximum aperture value as Av, and the above change in aperture value due to the attachment of the o-lens adapter as the limit due to the fact that the maximum aperture of the interchangeable lens is limited when the lens adapter is attached. If the aperture value is A v c, then Avo + k) When Avc, Bv - (Avo 10k) Avo + k l When Avc, By - Avc Furthermore, attach a lens adapter that is not equipped with an automatic aperture mechanism. By-Avn is displayed when the user is wearing an interchangeable lens or an interchangeable lens is not attached. Here, A v n corresponds to the actual value when the lens is stopped down or the aperture value when the lens is not attached. Also, if only the lens is attached, By
-Avo data is output.

Here, to explain the relationship between Avn and Avc using a specific example, 1, for example, Fl, 4 (Avo=1) ~F
Assuming that when a teleconverter is attached as a lens adapter to a 16 (Av max 28) lens, the effective aperture value of the lens will become one stop smaller, the effective aperture value will be F2 (Av == 2). ~F22 (Av
= 9). Here, by attaching a teleconverter, the maximum aperture of the lens is limited, and for example, if the limited aperture value is F4 (Av=4), the effective aperture will be F4 to F22, and F1.4 to F1.4.
The aperture on the lens side between F4 (1≦Av<4) is disabled. On the other hand, F 3.5 (Avo = 3.5) ~
When a lens of F22 (Avmax = 9) and the above-mentioned teleconverter are attached, the effective aperture is F4.5.
(Av-4,5) to F32 (Av-210), and in this case, the limiting aperture due to the installation of the teleconverter is effective over the entire range.

24 is a data output device to which data Sv of the set film sensitivity is output, and the addition circuit 26 calculates the following based on the data from this data output device 24 and the A-D switching circuit n: By −(Avo+k) +5v= Ev-(Avo
10k) Bv −Avc + Sv = Ev −AV
CBv −Avn + Sv = Ev −AvnBv
−Avo+Sv=Ev−Av.

Perform one of these operations. The data calculated by this addition circuit 26 is sent to an exposure calculation circuit 40 and a multiplexer 4.
2.

The exposure calculation circuit 40 further includes decoders 28 and 30°3.
Data from 2 and 34 are input. Here, from the decoder path, data Avo for calculating the maximum aperture value of the lens is sent from the register REG5 in FIG. 1, and from the decoder path, data on the accessory type from the register REG3 in FIG. The data Avc of the limited aperture value due to the attachment of the accessory is sent from the decoder 32, and the data k of the amount of change in the aperture value due to the attachment of this accessory based on the accessory type data from the register REG3. However, the data Avs for calculating the set aperture value from the register REGIO in FIG. 1 is outputted from the decoder. 36 is a data output device that outputs data Tvs of the set exposure time, and this data Tvs is also input to the exposure calculation circuit 40. The blade is a one-code setting device, and when in exposure time priority automatic aperture control mode (hereinafter referred to as T priority mode), the aperture is automatically controlled according to the set exposure time, film sensitivity value, and subject brightness. is an aperture-priority exposure time automatic control mode (hereinafter referred to as A-priority mode) in which the terminal T becomes "High" and the exposure time is automatically controlled according to the set aperture value, film sensitivity value, and subject brightness. When , terminal A is “High”
become.

When in program control mode (hereinafter referred to as P mode) in which both the exposure time and aperture are automatically controlled according to the set film sensitivity value and subject brightness, terminal P is "High".
In addition, in a manual control mode (hereinafter referred to as M mode) in which both the exposure time and aperture are controlled by manual setting values, the terminal M becomes "High". These terminals T, A, P,
M is input to the exposure calculation circuit 40, and the exposure calculation circuit 40 calculates the mode corresponding to the mode designation signal from any of the terminals T, A, P, and M. Data is sent between the exposure time control devices and the exposure time display device 52 via the output terminal 0UT3 and the multiplexer 42, data for aperture control is sent from the output terminal OUT□ to each aperture control device, and data for aperture display is sent to the output terminal 0UT.
2 to the aperture display unit.

Next, the exposure calculation operation in each mode within the exposure calculation circuit 40 will be explained based on the flowcharts of FIGS. 6-1 and 6-2. In step #1, the open aperture value Avo + k based on the change in aperture value due to attaching the lens adapter is compared with the limited aperture value Avc due to attaching the lens adapter, and Avo + k)
If it is Avc, go to step #2 Avo + k
l If Avc, #move to that step. When moving to step #2, data Ev (Avo + k
), and in step #2 Ev − (Avo 1k) + (Avo + k
) -= Ev is calculated, and an exposure value Ev that is not affected by the open aperture value is calculated.

Continuing (In step #3, the mode is determined based on the mode designation signal of any terminal T, A, P, or M given from between the mode setting devices, and if it is T priority mode, go to step #4; If the mode is the mode, the process moves to step #14, if the mode is the P mode, the process moves to the step #24, and if the mode is the M mode, the process moves to the step #.

First, the case of the T priority mode from step #4 will be explained. In step #4, Ev - Tvs = Ave is calculated, and then the effective aperture values Ave and Av are calculated.

+ k , determine the magnitude relationship with Av max . Here, Avo + k l Ave −t= Av max
+ k, it means that control to this effective aperture value Ave is possible, and in step #6, the number of aperture stages, that is, (Ave - k ) - Avo is calculated, and the output terminal QUT 1 Outputs the data on the number of narrowing stages of the heel. This data is input for each diaphragm control device.

When the aperture is narrowed down based on this value, the aperture value of the lens alone becomes Ave -k, but since the lens adapter makes the aperture smaller by k, the effective aperture value becomes Ave.

Furthermore, the data Ave of the effective aperture value calculated in step #4 is output to the output terminal 0UT2 in step #7,
This effective aperture value is displayed on the aperture display device 56. #8
In step , data Tvs of the set exposure time is output to the output terminal 0UT3. Then, the process returns to step #1 and the same operation is repeated until the shutter release is performed.

If it is determined in step #5 that Ave (Avo + k), it is impossible to control the aperture to the effective aperture value of Ave, so Av.

#14 uses the data of the set aperture value Avs and shifts to Mono9 priority mode. Also, if Ave)Ay max + k is determined in step #5, the aperture cannot be controlled as described above, so Avmax is set as the set aperture value and the mode shifts to A priority mode.

Note that Ave (Avo + k or Ave > A
When v max + k is determined, the exposure time determined based on the newly set Avo or Aymax is Tv = Tvmin (maximum exposure time) or Tv =
If the exposure time is outside the range of exposure time that can be controlled by Tv max (minimum exposure time), photographing with proper exposure will not be possible. In these cases, the effective aperture value is Avo + k,
Exposure control is performed by setting the exposure time to Tvmin, and an under-warning is performed, and the effective aperture value is set to Avma.
It is desirable to perform exposure control by setting x 10k and exposure time to 'l'vmax, and also to issue an over warning.

Next, the A priority mode from #14 will be explained.

First, in step #14, the calculation Ev - (Avs + k) = Tv is performed. As described above, Avs + k is the effective aperture value Ave when the aperture value of the lens is controlled to Avs. Next, it is determined whether the calculated exposure time data Tv is within a controllable range, and Tv min l Tv l
If Tv max, data on the number of aperture stages of AVS-Avo is sent from output terminal OUT'1 to A for each aperture control device.
Data on the effective aperture value of vs + k is output from the output end 0UT2 to the aperture display device 56, and data on the exposure time Tv is output from the output end 0UT3 between the exposure time control devices and the exposure time display device 52, and then proceed to step #1. return. When Tv (Tv min) is determined in step #15, Tv min is set as the exposure time and #4
Shifts to T priority mode from step . At this time A
If vs=Avo, proper exposure control is impossible, so it is desirable to issue an under-exposure warning and perform control based on Avo and Tvmin. On the other hand, Tv ) Tv m
When ax is determined, Tv max is set as the set value and the mode shifts to T priority mode. In this case as well, Avs = Av max
If it is determined that , it is desirable to issue an over warning and control the exposure based on Av max and TV max.

Next, the P mode from #24 will be explained. First #2
In step 4, p-Ev=Ave (0(p(1) Ev -Ave = Tv is calculated, and then it is determined whether Ave is within a controllable range. Then, Avo + k 4 Ave 4 AV mox +
If k, then (Ave −k ) −Av.

It is output to the data output terminal OUT of the number of narrowing stages.

This data is the number of aperture stops on the lens side to achieve the calculated effective aperture value Ave, as in the case of the T priority mode. Next, the effective aperture value data Av
e to the output terminal OUT, . . . and the calculated exposure time data to the output terminal 0UT3, and the process returns to step #1. Also.

If A, ve (Avo + k), Avo is used as the set aperture value data in step #1, and the mode returns to the priority mode from #14. Conversely, if Ave) Av max is 10, In step #32, Av max is used as data of the set aperture value and the process shifts to the priority mode from #14.

Next, in the case of M mode, the output end 0UT1 contains data Avs-Avo of the number of aperture stages based on the set aperture value AVS.
However, the effective aperture value Avs + k is at the output end 0UT2.
The set exposure time data Tvs is outputted to the output terminal 0UT3, and the process returns to step #1.

Now, in step #1, if it is determined that ALVO+k 4 Av( , then the data input from the adder circuit 26 to the arithmetic circuit 40 is Ev-Avc, so (Ev - Avc ) + Avc = Calculation of Ev is performed in step #39, and in step #39, exposure control shade is determined, and the flow shifts to the calculation flow for each mode shown in FIG. 6-2.

In Figure 6-2, in the case of T priority mode, first #40
In step , Ev - Tvs = Ave is calculated, and then it is determined whether Ave is within a controllable range. At this time, if Avc 4 Ave l Av max + k, then (Ave -k) -Avo, Ave, T as in the case of the T priority mode in Figure 6-1 below.
The data of vs is sent to the output terminals OUT, , 0UT2,
Output to 0UT3 and return to step #1. Also, Av
e (If Avc, set Avc k as the set aperture value and shift to the A priority mode flow from #61. At this time, if Tvs = Tv min, proper exposure is impossible, so perform an under warning. ,Avc-k
, It is desirable to perform exposure control using Tvmin as a set value. on the other hand.

Ave) If Av max + k, the flow shifts to A priority flow from #51 with Avmax set as the aperture value, but in this case as well, 'll'v
If s = Tv max, it is desirable to issue an over warning and perform exposure control using Av max and Tv max as set values.

Next, the operation in the A priority mode from step # will be explained. First #Blade step Avs 10k
When it is determined that 4 Avc, Ev-(Avs+k)=Tv is then calculated, and it is determined whether or not Tv is within a controllable range. At this time, if Tv min l TV I Tv max,
The data of Avs −Avo, Avs + k, and Tv are sent to the output terminals OUT□, 0UT2.0UT3, respectively.
output and return to step #l. Also, if Tv (Tv min ) is set, Tvmin is set as the exposure time and the flow shifts to the T priority mode from 44240;
) If TV max is reached, Tv max is set as the set exposure time and the flow shifts to the T priority mode.

At this time, if Avs = Av max, an over warning is given and Av max, Tv max
It is desirable to control exposure using

If it is determined that Avs + k (Avc) in step #, the flow moves to #61 and below.In this case, the set aperture value of the lens aperture is greater than the limited aperture value due to attaching the lens adapter. Since the effective aperture value is on the open side, the actual effective aperture value is Avc8. In this case, Avc is reset as the effective aperture value and the calculation Ev - Avc = Tv is performed, and Tv is the control Determine whether it is within the possible range.If Tv min l Tv l Tv max, then
Shifting to step #64, the output terminal OUT outputs data for the number of aperture stages of 0, the output terminal 0UT2 outputs data for the effective aperture value Avc, and the output terminal 0UT3 outputs data for the exposure time Tv. and returns to step #1. Also.

When it is determined that Tv (Tv min ), the set effective aperture value is the widest aperture value Avc, so proper exposure is impossible.
In this case, Tvmin is set to the value calculated in step #63, and the process proceeds to step #64. Note that at this time, it is desirable to also issue an under warning.

On the other hand, if Tv > Tv max, TV max is set and the flow shifts to T priority mode.

In the case of P mode, p-Ev-Av is set in step #70.
e EV -Ave = Tv is calculated, and the following operations are similar to those in the T priority mode from #41.

In the case of M mode, in step #80, Avs + k
) Avc, the process moves to steps #81 and below, and the number of aperture stages Avs - Avo, effective aperture value, A
vs 10% exposure time Tvs data to the respective output terminals OU
T1. OUT 2. Output to OUT 3 and return to step #l. On the other hand, if it is determined in step #80 that Avs + k (Avc), the process moves to step #e, where the number of aperture stages is 0 and the effective aperture value Av (:.

Exposure time Tvs is output terminal 0UT1, 0UT2, 0UT3
is output, and the process returns to step #1.

Note that if only an interchangeable lens is attached, the first
The output of register REG3 in the figure is "oooooo".

The photometric data is By-Avo. In this case, from the decoder I, 32, Avc =: O, k = O
If the data is outputted, normal exposure calculation according to the aforementioned flow (Fig. 6-1) will be performed.

The remaining portions of FIG. 5 will be explained again. Decoder 4
4, it is determined whether the lens adapter is equipped with an automatic aperture mechanism or not based on the lens adapter type data from the register REG3. And as shown in Table 3,
Data “01001”, “01010”, “01” indicating that the accessory is not equipped with an automatic aperture mechanism
011”, “01100” is input, the decoder 4
The output of No. 4 becomes "High", and becomes "Low" when other data is input. Also.

No lens is attached, so register R in FIG.
When the check code 11100" data is not input to EG, the output of AND circuit AN16 is "Lo".
w'', the input level to the OR circuit 46 in FIG. 5 is '
Therefore, when a lens adapter without an automatic aperture mechanism is attached or an interchangeable lens is not attached, the output of the OR circuit 46 becomes "High".
At this time, since there is no need to perform diaphragm control, this output is given to each diaphragm control device and the control device 1 is inoperative.

In addition, the aperture display does not need to be displayed except when displaying the set aperture value, so the aperture is automatically controlled.
In the priority mode and P mode, the AND circuit 62 is activated by the output of the OR circuit ω and the output of the OR circuit 46.
The output becomes “High”.

The aperture display in the aperture display device I is made inactive.

Next, regarding the exposure time, since the lens adapter does not have an automatic aperture mechanism, the output of the OR circuit 46 is "High".
and the selected mode is other than M mode (terminal M is “L”)
ow"), the AND circuit 48 outputs "High"
signal is output. This signal is sent to the selection terminal SE of multiplexer 42, in this case.

The Ev-Avn data from the addition circuit 26 based on the photometry of the subject light that has passed through the manually narrowed-down lens diaphragm, that is, the stop-down photometry, is output as is. Then, this data is displayed as a proper exposure time on the display device 52, and the exposure time is further controlled by the exposure time control device based on this data. That is, the mode becomes an aperture-priority exposure time automatic control mode using aperture metering. On the other hand, even if the output of the OR circuit 46 is "High", when it is in M mode (terminal M is "I-l-1i"), the AND circuit 48
The output becomes @Low', and the data of the set exposure time Tvs from the exposure calculation circuit 40 is output as is from the multiplexer 42, and display control is performed based on the data Tvs. Also, the output of the OR circuit 46 is “Low”.
'', display control is performed based on data from the exposure calculation circuit 40.

In a zoom lens with a variable focal length, a typical focal length of at least 3 is displayed on the focal length adjustment setting member.
Although it is possible to infer the set focal length to some extent, it is also possible to find out more specific focal length values, or to what extent within the adjustable focal length range the set focal length falls. It is impossible to judge at a glance.

An embodiment in which the above information regarding the set focal length is made visible within the finder of the camera will be described below. Here, register REG7 in FIG. R.E.
G8. REG10. A display based on data indicating the minimum focal length, maximum focal length, set focal length, and percentage of the set focal length read into the REG 13 will be described.

FIG. 7 is a block diagram for carrying out a first example of such a display, and FIG. 8 is a diagram showing a display section of the first example. Further, Tables 7-1 and 7-2 show values regarding focal lengths of various zoom lenses.

Table 7 Table 7 In Tables 7-1 and 7-2, the lens type indicates the range from the shortest focal length to the longest focal length of various zoom lenses, and the focal length is the setting input to each zoom lens. It shows the focal length. As mentioned above, this data is input with commonly used focal length data, but since the set focal length data from block 12 in Figure 3 is 4 bits, it is more detailed than that shown in Table 5. It is also possible to create separate data.

The IO/Iog2 column is the 10/log of each setting focal length.
The value of 2f is shown, and the difference column shows the shortest focal length f
When min is 10・log2 f-10・log2
The 1 display data column that shows the value of f min is "0001" if the value is 0 to 19, 100010 if it is 20 to 39, and @ooioo', 60 if it is 40 to 59.
~79 is "01000", 80 ~ ioo is -100
00”.

In order to obtain these various types of data by dividing them into smaller pieces, input the data from block 12 in Figure 3 directly into the camera body, and obtain the data corresponding to the shortest focal length and longest focal length (the attached lens). data for identification)
and setting data (data from block 12 in FIG. 3), the set focal length, 10·Iog2, difference data, and display data may be obtained.

In FIG. 7, the data on the shortest focal length from the register REG7 is converted into display data by the decoder DE1o and sent to the display device DP1, where the shortest focal length is displayed numerically as shown in FIG. The longest focal length data from the register REG8 is converted into display data by a decoder DE11, and the longest focal length is displayed numerically on a display device DP2 as shown in FIG. Also, register REG
□The data of the set focal length of 1 is converted into display data by the decoder DE1□ and sent to the display device DP3.
As shown in the figure, numbers are displayed on the display device DP3. Also, the % data from register REG13 is displayed on the display device DP.
4, and one of the display sections e□ to e5 is displayed.

That is, "00001" is el, "00010" is e2, "00100-" is e3, -01000' is e
4, -10000", e5 is displayed to indicate whether the set focal length is a percentage of the overall performance. Note that 60 indicates the field of view in the finder.

FIG. 9 is a block diagram showing a second example for displaying the set focal length in the finder, and FIG. 10 shows an example of the display section. Decoders DE15 and DE,
6 is the data of the maximum focal length f max and the set focal length f from registers REG8 and REGll, respectively.
This is a decoder that converts data into data of g2f max and lOlo-1of, and these two decoders DE ts
, DE ta is input to the subtraction circuit 70, and data of 10·Iog2(f max/f ) is output. This data is input to the decoder 72 and sent to one of the terminals f corresponding to the pig from the subtraction circuit 70. −
f24 becomes 'High'.In other words, if the data from the subtraction circuit 70 is 24, the terminal f24 is set, if the data is 2, the terminal f23 is set, and so on, if the data is 1, the terminal f1 is set, and if the data is 0, the terminal f is set.
. becomes “High”. and terminals f24 to f2
□ is connected to terminal g1 through a diode, and terminal f2
1 to f19 are connected to terminal g2 via a diode, and terminal f1 is connected to terminal g2 through a diode.
8 to f13 are connected to terminal g3 via a diode, f12 to f
6 is connected to g4, and f5 to fo are connected to g1. The display device 74 then displays one of the display lines h11, h2+h3, and h4 provided within the viewfinder field of view ω in FIG. 10 in accordance with the outputs of the terminals g1 to g5.

The display line h□ to h4 in Fig. 10 indicates the field frame visible within the viewfinder field of view when the focal length is set to the maximum focal length for the set focal length.
Taking a Ku~500 mm zoom lens as an example, when the set focal length is between 500 mm and 360 mm, terminal g4 becomes "High" and no line is displayed.

For 300 to 250 uL, terminal g4 becomes "High" and line h4 is displayed, and for 200 to 180 uL, terminal g
3 becomes "High h" and line h3 is displayed,
For 135 to 120 jul, terminal g2 is “High h”
When the voltage is less than 120IIjI, the terminal g□ becomes "High h" and the line h1 is displayed. Therefore, in this example, it is possible to display how much further close-up is possible by shifting the focal length to the long focal length side. Note that 1 display section DP1.
In DE2 DE3 and DE3, the shortest focal length and longest focal length are displayed numerically as in the first example.

Note that the configurations of shift registers SR2 and SR3 in FIGS. 2 and 3 are TA7. At the timing when TL7 is °High', the data of ROM ROl and RO2 are taken in parallel, respectively, and from the timing of the rise of primary TAo and TLo, the data is transferred bit by bit to the camera body side11.
The specific configuration of this shift register is as follows. That is, a flip-flop is provided for each bit to which the data of each bit input in parallel is preset, and the output terminal of the clip-flop corresponding to the lower bit is connected to the flip-flop corresponding to the bit immediately above the lower bit. - Connect to the input terminal of the flop, and sequentially transfer the data preset in each of the 7 flip-flops from the lower bit to the upper bit in synchronization with the clock pulse. Furthermore, apart from these flip-flops, another 7-lip-flop is provided, and the flip-flop
When the input terminal of the flop is connected to the output terminal of the flip-flop corresponding to the most significant bit, this separately provided flip-flop outputs the captured data bit by bit with a delay of one clock pulse. become.

In the above explanation, the reading start signal 5tart is applied to the flip-flop FF by closing the photometry switch S1.
□, but instead of going to the trouble of outputting it through the flip-flop FF1, we read the power supply line +V generated by the closing of the photometric switch S1, set it as the start signal 5tart, and connect this voltage signal. It may also be transmitted to the accessory via the terminal JB3. Note that the timing at which the reading start signal 5tart is generated is not limited to the time when the photometry switch S□ is closed, but may be generated at any time prior to the start of exposure of the camera body. Further, in the above-mentioned embodiment, the circuit section of the present invention is configured with a logic circuit for convenience of explanation, but this may be replaced with a so-called microprocessor CPU to configure the above-mentioned embodiment so that the operation is controlled in a sequential manner. Needless to say.

〔Effect of the invention〕

As explained above, according to the present invention, when the photographic optical system attached to the camera body is not equipped with an automatic aperture mechanism that operates under the control of the camera body, various exposures prepared on the camera body side can be used. Since the control modes that do not operate properly are automatically restricted, the photographer does not have to pay attention to whether or not the photographic optical system installed has an automatic aperture, and can always use proper exposure control. Can be photographed.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the camera body side of the present invention, and FIGS. 2 and 3 are accessories.
FIG. 4 is a diagram showing a specific circuit configuration of the setting device; FIG. 5 is a block diagram showing the configuration of an exposure control section on the camera body side to which the present invention is applied; 6th-
1 and 6-2 are flowcharts, and FIG. 7 is a block diagram showing another application example of the present invention in which when the accessory is a zoom lens, the set focal length can be displayed within the camera body. FIG. 8 is a diagram showing an example of the display, FIG. 9 is a block diagram showing another embodiment of FIG. 7, and FIG.
The figure shows an example of the display. ROl, R02...Fixed memory circuit, CO4+
Cos + CO7+ DE 3 + DE 4 )
MP 1 + MP 2... Address designation device, 5R21SR3, AS□, AS2... Information transmission device, SR1, REG1 to REG13... Information reading device, Sl, BT□ , 1... Read signal generation circuit, 10, 11, 12......
...Setting device, VT...Sliding
Member, PAo-PA3. lN2o-IN23.
EOo-EO2,... Signal output member. Applicant Nolta Camera Co., Ltd. Figure 1O

Claims (2)

[Claims] (1) Multiple photographic optical systems are selectively attached to the camera body, including an automatic aperture photographing optical system whose aperture diameter is automatically determined to a desired value under control from the camera body. In a camera system in which a camera body selectively operates in a plurality of exposure control modes including a mode for automatically determining an aperture diameter of a photographing optical system, a selection means for selectively selecting one of the plurality of exposure control modes; , a determining means for determining whether or not the attached photographic optical system is of an automatic aperture type operated by control from the camera body; and a determining means for determining whether a non-automatic aperture type photographing optical system is attached. and limiting means for limiting the number of exposure control modes that can be selected by the selection means to be less than the number of exposure control modes when it is determined whether an automatic aperture type photographing optical system is installed. A camera system featuring: (2) Multiple exposure control modes include a first mode that automatically controls the aperture diameter based on the photometric value of the subject brightness that has passed through the photographic optical system, and a first mode that automatically controls the aperture diameter of the photographic optical system. The limiting means prohibits selection of the first mode when a non-automatic diaphragm type photographing optical system is installed. 2. The camera system according to claim 1, wherein the selection means is controlled so as to.