JPH054652B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an interchangeable lens camera system that efficiently transmits lens characteristic data stored in an interchangeable lens attached to an interchangeable lens camera to the camera body. [Prior art] Fixed information storage (hereinafter referred to as ROM) is provided in the interchangeable lens attached to the camera body.
A device that stores lens-specific characteristic data (for example, open aperture value, maximum aperture value, etc.) in a ROM, reads out this data by specifying a ROM address, and uses it to control the camera system. , was previously proposed by the present applicant (see Japanese Patent Application Laid-Open No. 108628/1983). Since the lens-specific characteristic data stored on the interchangeable lens side is used in the control system on the camera body side, the number of types of data is determined by the specifications of the daytime control system.
That is, in a control system that performs only basic control, the number of types of data is small, but as the control system performs more advanced control, the number of types of data required increases. For example, the number of types of lens-specific characteristic data differs between variable focal length lenses and fixed focal length lenses. That is, in a variable focal length lens, not only the focal length changes, but also the open aperture value changes depending on the set focal length, so the number of types of data is greater than that in a fixed focal length lens. [Problems to be Solved by the Invention] As described above, lenses that should be stored on the interchangeable lens side depend on whether the control system on the camera body side performs only basic control or the control system that performs more advanced control. Although the number of types of unique characteristic data varies, all types of data are stored on the interchangeable lens side so that it can be applied to any camera body control system, and the camera body side control system The common method is to select and use the required data from all types of transmitted data. In addition, in order to simplify the configuration for reading lens-specific characteristic data stored on the interchangeable lens side and transmitting it to the camera body, even if the number of types of data to be read is different, it is necessary to It is desirable to use the data reading means. Therefore, if the number of data types differs depending on the type of lens, for example, data included in a variable focal length lens but not included in a fixed focal length lens, the number of data types included in that lens may differ depending on the type of lens. The problem can be temporarily solved by making the number of types of lens-specific characteristic data stored on the interchangeable lens side the same for all interchangeable lenses, such as by storing meaningless data in the data portion of the types that do not exist. can. However, the time required to read the lens-specific characteristic data stored on the interchangeable lens side and transmit it to the camera body side is a considerable amount of time within the information processing time within the camera system. Reading out and determining such meaningless data or data that is not used by the control system of the camera body will hinder the speeding up of information processing within the camera system. This invention aims to solve the above problems. [Means for Solving the Problems] The present invention solves the above problems, and includes a first type of lens in which a first data group and a second data group unique to an interchangeable lens are stored, and the first type of lens. In an interchangeable lens camera system in which a second type of lens in which only a data group is stored is selectively attached to a camera body, a first data storage area that stores the first data group and a second type of lens that stores the second data group are provided. a second data storage area for storing a group of data, and a reading means for reading the data group from the interchangeable lens based on a clock signal and storing it in the first and second data storage areas; determining means for determining whether the interchangeable lens is a first type of lens or a second type of lens; and when the determining means determines that the first type of lens is worn, the first and second lenses are A data group is read from the interchangeable lens and stored in the first and second data storage areas, and when it is determined that the second type of lens is attached, only the first data group is read from the interchangeable lens. and read control means for controlling the reading means so as to store the data in the first data storage area. In this embodiment, the first type of lens is, for example, a variable focal length lens,
The second type of lens may be, for example, a fixed focal length lens. [Function] Determines whether the interchangeable lens attached to the camera body is a first type of lens or a second type of lens,
If it is determined that the first type of lens is being worn, the first and second data groups are read from the interchangeable lens and stored in the first and second data storage areas, and the second type of lens is attached. If it is determined that the interchangeable lens is worn, only the first data group is read from the interchangeable lens and stored in the first data storage area. Thereby, when the second type of lens is attached, the types of data to be handled can be reduced, and information processing within the camera system can be speeded up. Embodiment 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 lens adapter attached to the camera body, and FIG. 3 is a circuit diagram of the lens adapter installed in the camera body. FIG. 2 is a circuit diagram inside an interchangeable lens. In Figure 1, BA is the power battery,
_S1 is a photometry switch that is closed in conjunction with a photometry button (not shown). When this photometric switch _S1 is closed, the transistor _BT1 becomes conductive, and power is supplied from the power supply battery BA to the power-on reset circuit 1, the exposure control section (Fig. 5), etc., which will be described later, via the power supply line (+V). It is done. Power-on reset circuit 1
starts supplying power from the power line (+V),
Outputs the power-on reset signal POR, and uses this signal POR to reset the flip-flop FF ₁ and the register.
REG ₂ to REG ₁₃ , D flip-flop DF ₁ and frequency divider DI ₁ are reset. In addition, the counter, flip-flop, register, decoder, etc. shown in the figure are constantly powered by a battery via the power line (+E).
Power is being supplied from BA. Furthermore, when the photometric switch S ₁ is closed, the inverter IN ₁
The output of D flip-flop DF1 becomes "High" and the Q output of D flip-flop _DF1 becomes "High" at the rising edge of the next clock pulse CP from the oscillator PG.
AND circuit AN ₁ gate is opened AND circuit
A clock pulse CP is now sent from AN ₁ to the frequency divider DI ₁ . At the same time, this "High" signal is also given to the one-shot circuit OS ₁ , and a "High" pulse is sent from the one-shot circuit OS ₁ for a predetermined period of time to the flip-flop FF ₁ via the OR circuit OR ₁ .
sent to. This pulse sets flip-flop _FF1 and makes the Q output "High". Additionally, this "High" signal is sent to the inside of the camera body and accessories, and serves as a start signal to start the reading operation. This start signal (Start) causes the AND circuit to
The gate of AN ₂ is opened, the reset state of counters CO ₁ and CO ₂ is released, and the decoder is
DE ₁ becomes ready for output. Counter CO ₁ counts clock pulses CP from oscillator PG sent via AND circuit AN ₂ and decoder DE ₁
According to the output of this counter CO ₁ output terminal TB ₀
~ Set one of TB ₇ to “High”. Table 1 shows the relationship between the input and output of this decoder _DE1 .

[Table] Lens adapter terminals JA ₁ , JA ₂ ,
JA ₃ , JA ₄ , and JA ₅ are the terminals JB _{1 and} JA 5 on the camera body side, respectively.
Connected to JB ₂ , JB ₃ , JB ₄ , and JB ₅ , JA ₁ is the terminal that receives the power line (+E) from the camera body, JA ₂ is the terminal that receives the clock pulse CP from the camera body, and JA ₃ is the terminal that receives the clock pulse CP from the camera body. JA ₄ is the terminal to which the reading start signal (Start) is input from the camera body, and JA 5 is the common body ground terminal, and JA ₅ is the terminal that outputs data from the lens adapter to the camera body. Note that the terminals JL ₁ to _{JL 5} of the interchangeable lens in Figure 3 are the second terminals.
These terminals are connected to the camera body in the same way as the terminals JA ₁ to _{JA 5} of the lens adapter shown in the figure. When a reading start signal (Start) is input from the terminal JB ₃ of the camera body via the terminal JA ₃ or JL ₃ , the counters CO ₃ , CO ₄ and D flip-flop are input in FIG.
The reset state of DF ₃ is released and decoder DE ₃ and
The ROM (RO ₁ ) becomes ready for output. Also,
At the same time, this signal (Start) is a one-shot circuit.
It is also applied to OS ₄ , and the flip-flops FF ₂ and FF ₃ are reset by the pulse from the one-shot circuit OS ₄ . Similarly, in Figure 3, the counter
CO ₅ , CO ₆ , CO ₇ , D flip-flop DF ₅ ,
The reset state of DF ₆ is released and decoder DE ₄ and
ROM (RM ₂ ) becomes available for output. Furthermore, flip-flops _FF4 , _FF5 , and _FF6 are reset by a pulse from the one-shot circuit _OS3 . The counter CO ₃ in FIG. 2, the decoder DE ₃ and the counter COO ₅ in FIG. 3, the decoder DE ₄ as the counter CO ₁ in FIG.
It has the same configuration as decoder DE ₁ , and the respective output terminals TA ₀ to TA ₇ , TL ₀ of decoders DE ₃ and DE ₄
~TL ₇ is the output terminal of decoder DE ₁ TB ₀ ~ _{TB 7}
A pulse is output at the same timing as
The camera body and accessories are synchronized.

【table】

【table】

【table】

【table】

【table】

[Table] Tables 2-1 and 2-2 show the relationship between addresses and the contents of various data in the ROM where various data of accessories are stored, and Table 3 shows the relationship between the encoded data and the data indicated by the data. It shows the relationship with the content. In the following operation explanation, this table 2-
1, 2-2, and Table 3. Second
In the figure, when the read start signal (Start) is output, the flip-flop FF ₂ is reset via the one-shot OS ₄ , so even if the reset state of the D flip-flop DF ₃ is released, its output remains unchanged. It remains "High" and the switch circuit _AS1 remains conductive. 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 CO ₄ becomes "01" by the TA ₁ pulse from decoder DE ₃ , "0000001" is given as the address of ROM (RO ₁ ), and the lens adapter check code "11100" is stored. The address specified is specified, and data “11100” is output from the ROM (RO ₁ ). and,
The flip-flop _FF3 is set by the AND circuit _AN23 at the falling edge of the clock pulse CP output while the terminal _TA1 is "High", and the AND circuit AN23 is set by the AND circuit AN23.
It is reset by AN ₂₂ at the fall of the clock pulse CP output while the terminal TA ₂ is "High".
Therefore, the Q output of flip-flop FF ₃ is the terminal
It becomes "High" only from the falling point of clock pulse CP while TA ₁ is "High" to the falling point of clock pulse CP while terminal TA ₂ is "High", and the rising edge of clock pulse CP during this period, i.e. , data from the ROM (RO ₁ ) is loaded in parallel into the shift register SR ₂ when the terminal TA ₂ rises to “High”. 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 upper bit as described below, and is transmitted through the switch circuit AS ₁ and the terminals JA ₅ and JB ₅ into the shift circuit shown in FIG. It is taken into register SR ₁ . Here, the shift register _SR1 sequentially takes in data from the terminal _JB5 bit by bit in synchronization with the falling edge of the clock pulse CP. 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 the clock pulse CP while _TB3 is “High”.
It is read into the shift register SR ₁ on the camera body side at the falling timing of TA ₄ , TA ₅ ,
One bit is sent at each timing of TA ₆ and TA ₇ . In this way, reading one piece of data is completed at the falling edge of the clock pulse while TB ₇ is “High,” and at the next rising edge of terminal TB ₀ , the output data of shift register SR ₁ is transferred to register REG. ₁ in parallel. The decoder DE ₂ on the camera body side has the input and output relationships shown in Table 4.

[Table] Here, the counter CO ₂ whose output is given as the input of the decoder DE ₂ counts one by one at the rising edge of the terminal TB ₇ . First, when the first data, that is, the check data, is latched into the register REG ₁ at the timing when the terminal TB ₀ rises, the terminal d ₀ of the decoder DE ₂ is at "High". Therefore, the rising signal of the terminal _TB1 is applied to the latch terminal of the register _REG2 via the AND circuit _AN3 , and the data from the register _REG1 is latched in this register _REG2 . This register REG ₂
The output of AND circuit AN ₁₅ determines whether it is "11100" or not. If the lens adapter is attached and it is "11100", the output of AND circuit AN ₁₅ is "High" and the lens adapter is not attached. When the signal becomes “Low”. The output of this AND circuit _AN15 is given to a display section (not shown) that displays whether or not a lens adapter is attached. In Figure 2, at the next rising edge of terminal TA ₁ , the output of counter CO ₄ becomes “10”, and ROM (RO ₁ )
The address “0000010” is specified. Then
The ROM (RO ₁ ) outputs data indicating the type of lens adapter, as shown in Table 2-1. As shown in Table 3, this data is predefined such as "00001" for an automatic diaphragm interlocking type bellows and "00010" for an automatic iris interlocking type reverse adapter. This data is similar to the above,
When the terminal TB ₀ becomes "High", it is latched to the register REG ₁ of the camera body, and at this time, the output of the counter CO ₂ becomes "0010" and the terminal _{d 1} of the decoder DE ₂ becomes "0010" as shown in Table 4. Since it is “High”, register REG ₃ is set to register REG _1.
Data from is latched. Furthermore, since the output of the counter _CO4 becomes "10", a "High" pulse is output from the one-shot circuit _OS3 , and the flip-flop _FF2 is set. Then, at the next time when the terminal TA ₀ rises to "High" (at this time, the sending of the lens adapter type data is completed), the D flip-flop DF ₃ is connected to the D input (that is, the flip-flop FF ₂ (Q output) is set to "Low" and the switch circuit _AS1 is made non-conductive so that no data is transmitted from the lens adapter. Similar to the counter CO ₄ in Figure 2, the counter CO ₆ in Figure 3 also counts the rising edge of terminal TL ₁ , and when the count output reaches "010", the AND circuit
The output of AN ₂₅ rises to "High", a "High" pulse is output from one-shot circuit OS ₆ , and flip-flop FF ₄ is set. Then, similar to the D flip-flop DF ₃ in Figure 2, the Q output of the D flip-flop DF ₅ becomes "High" at the rising edge of the terminal TL ₀ , the switch circuit AS ₂ becomes conductive, and the data from the interchangeable lens is output. The state becomes ready for sending. Then, the counter starts at the next rising edge of terminal TL ₁ .
The output of CO ₆ becomes “011”. This counter CO ₆
The 3-bit output from the multiplexer MP ₂
is given to the lower 3 bits of the _β1 input. At this time, the Q output of the D flip-flop _DF6 is still "Low", so the multiplexer _MP2 outputs data "0000011" from _β1 , and this data becomes the address signal for the ROM ( _RO2 ). Then, as shown in Table 2-1, check data "11100" is output from the ROM (RO ₂ ), and is read into the register REG ₄ in FIG. 1 in the same manner as described above. In addition, the AND circuits AN ₂₈ , AN ₂₉ ,
The OR circuit OR ₄ , flip-flop FF ₆ , and shift register SR ₃ are the circuit AN ₂₃ and the shift register SR 3 shown in FIG. 2, respectively.
The circuit is similar to AN ₂₄ , OR ₃ , FF ₃ , and SR ₂ . The data read into register REG ₄ is determined by the AND circuit AN ₁₆ 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
The output of AN ₁₆ becomes "High", the gate of AN ₁₇ is opened, and the pulse from terminal TB ₂ is output as the read end signal end ₁ . Thereafter, each time the terminal TL ₁ rises to “High”, the output of the counter CO ₆ becomes “100”, “101”, “110”, “111”, and the output from the multiplexer MP ₂ is “0000100”, “0000101”. ，
Address data “0000110” and “0000111” are output sequentially. Here, as shown in Table 2-1,
The above address of the ROM (RO ₂ ) stores data on the open aperture value Av ₀ , minimum aperture value Avmax, wide side focal length, and tele side focal length of the interchangeable lens. To explain specifically using Table 3, the aperture value data is a general aperture value that increases in 0.5Ev pitch from F1.2, that is, from F1.2 to F32 is "00000" to "10011". , the aperture value F1.8~F6.9, which does not correspond to the above 0.5Ev pitch aperture value and often exists as the maximum aperture value of the lens, is “10100”~
Each is defined in “11110”. Further, the focal length data is classified into commonly used general focal lengths from 8 mm or less to 1000 mm or more, as shown in Table 3, and data from "00000" to "11110" are defined. For the focal length data, the shortest focal length data for the wide side is stored in the address “0000110” for the zoom lens, and the data for the shortest focal length on the wide side is stored in the address “0000111” for the zoom lens.
The longest focal length data on the side is memorized. On the other hand, in the case of an interchangeable lens with a fixed focal length, the focal length data is stored as is at the address "0000110", and data "11111" indicating that the focal length is fixed is stored at the address "0000111". Therefore, by sequentially outputting the above address data "0000100" to "0000111" from multiplexer MP ₂ , data on the maximum aperture value, minimum aperture value, wide side focal length, and tele side focal length of the interchangeable lens is sent to the camera body. side registers REG ₅ , REG ₆ ,
Read sequentially into REG ₇ and REG ₈ . Also, the AND circuit AN 18 determines whether the output of the register REG ₈ into which the data on the Tele side is read is " ₁₁₁₁₁ ".If the focal length of the interchangeable lens is fixed, the output of the AND circuit AN ₁₈ becomes “High”. And D flip flop
DF ₂ takes in the D input (ie, the output of the AND circuit AN ₁₈ ) at the rising edge of the terminal TB ₂ of the decoder DE ₁ when the terminal d ₆ of the decoder DE ₂ is set to "High". In Figure 3, the output of counter CO ₆ is “111”
When this happens, the output of the AND circuit _AN26 rises to "High", and the one-shot circuit _OS7 outputs a "High" pulse. This pulse sets the flip-flop _FF5 , and the Q output of the D flip-flop _DF6 becomes "High" at the next rising edge of the terminal _TL0 . By this AND circuit AN ₂₇
The gate of is opened, and the pulse from the terminal TL ₁ is input to the counter CO ₇ , and at the same time, the data of the β ₂ input is output from the multiplexer MP ₂ . When the Q output of the D flip-flop DF ₆ becomes “High” and a pulse from the next terminal TL ₁ is input to the counter CO ₇ , the output of the counter CO ₇ becomes “001” and the block is output from the multiplexer MP ₁ . The data input from 10 to _α1 is 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. This data is used for any interchangeable lens.
It is designed to output 4-bit data starting from "0000". This data is given to the lower 4 bits of the input β ₂ of the multiplexer MP ₂ , and the output of the counter CO ₇ is given to the higher 3 bits, so the output from the multiplexer MP ₂ is “0010000”.
One of the address data from "0011111" is output and input to the ROM (RO ₂ ).
ROM (RO ₂ ) address “0010000” ~
As illustrated in Table 2-1, the area "0011111" stores data on the photographing distance according to the amount of deviation of the distance setting member of the interchangeable lens from the ∞ position. Therefore, this data is read into register REG ₉ of the camera body. Next, when the output of counter CO ₇ becomes “010”,
Multiplexer _MP1 outputs the data input from block 11 to _α2 . This block 1
1 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 from "0000" no matter what type of interchangeable lens you use. Note that if it is an interchangeable lens with a fixed aperture (for example, a reflective telephoto lens), only data "0000" will be output. From multiplexer MP ₂ “0100000” ~
One data of "0101111" is output and this data is input to the ROM (RO ₂ ). ROM
(RO ₂ ) address area "0100000" to "0101111" stores data on the aperture value according to the number of stops from the open aperture value of the aperture ring of the interchangeable lens, as illustrated in Table 2-1. There is. Therefore,
The set aperture value data output from the ROM (RO ₂ ) is read into the register REG ₁₀ of the camera body. In Figure 1, when the set aperture value data is read into register REG ₁₀ , if the Q output of D flip-flop DF ₂ is "High", that is, the attached interchangeable lens is a fixed focal length lens. If it is determined that
The gate of AN ₂₀ is opened and a pulse from terminal TB ₂ is output as a read end signal end ₂ , 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 Figure 3, the output of counter CO ₇ is “011”
Then, multiplexer _MP1 outputs the data from block 12 to _α3 . 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, and similarly to blocks 10 and 11, 4-bit data starting from "0000" is output. Ru. The multiplexer _MP2 outputs one of the data from "0110000" to "0111111" from _β2 , and this data is input to the ROM ( _RO2 ). ROM (RO ₂ ) address “0110000” ~
As illustrated in Table 2-2, the area “0111111” stores data on the focal length setting according to the position of the focal length setting member, and this data
It is output from the ROM (RO ₂ ) and read into the register REG ₁₁ on the camera body side. Next, when the output of counter CO ₇ becomes “100”,
The data from α ₃ is also output from multiplexer MP ₁ , and the ROM (RO ₂ ) has “1000000” ~
One data of “1001111” is input.
As illustrated in Table 2-2, data △Av of the amount of change in aperture value due to changes in the focal length of the zoom lens is stored in the address area of this ROM (RO ₂ ) from “1000000” to “1001111”. This data is output from the ROM (RO ₂ ) and read into the register REG ₁₂ of the camera body. Next, when the output of counter CO ₇ becomes “101”,
Multiplexer MP ₁ outputs the data from block 12, which is also from α ₃ , and transfers it to ROM (RO ₂ ).
One of the data from “1010000” to “1011111” is input to “1010000” to “1011111”. This ROM (RO ₂ ) area has the zoom lens setting focal length f ranging from the shortest focal length f min on the Wide side to the longest focal length f on the Tele side.
Data indicating how much of the range (what percentage from f min to the long focal point side) is the value is stored. To explain this data in more detail, this data indicates that if the value of f - f min / f max - f min × 100% is 0 to 19%, it is in the region of 1 (“00001”), and in the range of 20 to 39%. If so, the area is 2 (“00010”),
If it is 40-59%, the area is 3 (“00100”), 60-59%
If it is 79%, the area is 4 (“01000”), 80 to 100
%, the data indicates that the area is 5 (“10000”). At the same time as the data indicating the above area is read into the register REG ₁₃ on the camera body side shown in FIG. 1, the AND circuit AN ₂₁ outputs the read end signal end ₃ , and the OR circuit OR ₃ outputs the read end signal end.
is output. This end signal end is OR circuit OR ₂
The signal is sent to flip-flop FF1 via the flip-flop _FF1 , and this flip-flop _FF1 is reset. Therefore, the reading start terminal (Start) becomes "Low", the counters CO ₁ , CO ₂ and the D flip-flop DF ₂ are reset, and the decoder DE ₁ is also disabled from outputting a timing signal. Similarly,
Counters CO ₃ , CO ₄ and D flip-flop DF ₃ in FIG. 2 are reset, and decoders DE ₃ ,
ROM (RO ₁ ) becomes unable to output. Furthermore, the counters CO ₅ , CO ₆ , CO ₇ and D flip
The flops DF ₅ and DF ₆ are reset, and the decoder DE ₄ and ROM (RO ₂ ) become unable to output.
As described above, the reading operation is completed. In Fig. 1, if the photometry switch _S1 remains closed after reading is completed, the Q output of the D flip-flop _DF1 remains "High", so the AND circuit is activated. AN ₁
The clock pulse CP continues to be input to the frequency divider _DI1 via the frequency divider DI1, and a clock pulse of, for example, 4 Hz is outputted from the frequency divider _DI1 . At the rising edge of this 4Hz clock pulse, the one-shot circuit OS ₂ outputs “High”.
The pulse is outputted and input to the flip-flop _FF1 via the OR circuit _OR1 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 frequency 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 (any one of the positions) by mechanically clicking the aperture ring 13 on the lens side. The continuity pattern CT is grounded, and the other continuity patterns PA ₀ ~
PA ₃ is connected to the power supply line (+E) via a resistor, respectively. Therefore, when the contact piece of the sliding member VT comes into contact with any of the conductive patterns PA ₀ to _{PA 3} , the conductive patterns PA ₀ to _{PA 3} are selectively short-circuited to the conductive pattern CT, and the conductive pattern PA in contact is ₀ ~
The outputs of inverters IN ₂₀ to IN ₂₃ connected to PA ₃ are selectively set to “High”. On the other hand, when the contact pieces of the sliding member are not in contact with the conductive patterns _PA0 to _PA3 , the outputs of the inverters _IN20 to _IN23 are both "Low". The output of the inverter IN ₂₃ is connected to the output terminal d ₃ and one input of the exclusive OR EO ₂ . The output of inverter IN ₂₂ is connected to the other input of exclusive OR EO ₂ , and the output of exclusive OR EO ₂ is
Connected to output terminal d ₂ and one input of exclusive OR EO ₁ . The output of inverter IN ₂₁ is connected to the other input of exclusive OR EO ₁ , and the output of exclusive OR EO ₁ is connected to output terminal d ₁ and one input of exclusive OR EO ₀ . . And the inverter
The output of IN ₂₀ is connected to the other input of Exclusive OR EO ₀ , and
The output of EEO ₀ is connected to output terminal d ₀ . The conduction patterns PA ₀ to PA ₃ are gray codes, and Table 5 shows the relationship between the inputs of the inverters IN ₂₀ to IN ₂₃ and the outputs of the terminals d ₀ to d ₃ at each position based on this code. . Further, Table 6 shows the number of narrowing stages at each position.

【table】

【table】

【table】

[Table] Below, the relationship between the set aperture value and the set position of the sliding member VT will be explained. For an F1.2 to F16 lens, if the aperture ring is set to F1.2 (Av=0.5), the sliding member VT is in position, and the number of aperture stages is 0 from terminals d ₃ to _{d 0} . If data “0000” is output and F1.4 (Av=1) is set, the sliding member VT is in the position and the terminal
From d ₃ to _{d 0} , data “0001” with the number of refinement stages 0.5
is output. Similarly, F13 (Av=7.5)
If set to , the number of narrowing stages is 7 from terminals d ₃ to _{d 0.}
Data “1110” indicating
8), 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 measures to be taken when no interchangeable lens is 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. (The aperture is smaller than the set aperture value.) Countermeasures have been taken. The photometry circuit 20 receives as input a photodetector PD that performs so-called TTL photometry that measures the subject light that has passed through the lens, and its output is converted into A by an A-D conversion circuit 22.
-D converted. This output indicates the subject brightness in Bv,
v The maximum aperture value is Avo, the amount of change in the aperture value due to the attachment of the lens adapter is k, and the aperture limit due to the restriction of the maximum aperture of the interchangeable lens by attaching the lens adapter is Avc, then Avo + k > Avc. When it is Bv-(Avo+k) When Avo+kAvc, it is Bv-Avc Furthermore, when a lens adapter without an automatic aperture mechanism is attached, or when an interchangeable lens is not attached, it is Bv-Avn. Here, Avn 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, Bv-Avo data will be output. Here, to explain the relationship between Avo+k and Avc using a specific example, for example, F1.4 (Avo=1) to F16
(Avmax=8) When a teleconverter is attached as a lens adapter to a lens, assuming that the effective aperture value of the lens becomes one stop smaller, the effective aperture value will be F2 (Av=2) to F22 (Av =9). Here, by installing a teleconverter, the maximum aperture of the lens is limited,
For example, if the limited aperture value is F4 (Av=4), the effective aperture will be F4 to F22, and F1.4 to F4 (1≦Av<
The aperture on the lens side between 4) is disabled. on the other hand,
When a lens of F3.5 (Avo=3.5) to F22 (Avmax=9) and the above-mentioned teleconverter are attached, the effective aperture will be F4.5 (Av=4.5) to F32 (Av=10), and in this case The aperture limit due to the teleconverter being installed is F4 (Av=4), so the aperture on the lens side is effective over the entire range. 24 is a data output device to which data Sv of the set film sensitivity is output, and an adder circuit 26
is based on the data from the data output device 24 and the A-D exchange circuit 22, Bv-(Avo+k)+Sv=Ev-(Avo+k) Bv-Avc+Sv=Ev-Avc Bv-Avn+Sv=Ev-Avn Bv-Avo+Sv= Perform one of the following operations: Ev−Avo. The data calculated by this adder circuit 26 is input to an exposure calculation circuit 40 and a multiplexer 42. The exposure calculation circuit 40 further includes a decoder 28,
Decoders from 30, 32, and 34 are input. Here, the decoder 28 sends the lens open aperture calculation data Avo from the register REG ₅ in FIG. 1, and the decoder 30 sends it to the register REG 5 in FIG.
Based on the accessory type data from REG ₃ , the limit aperture value Avc is determined by attaching the accessory, and the decoder 32 outputs the accessory attachment data based on the accessory type data from register REG ₃ . The decoder 34 outputs data k representing the amount of change in the aperture value caused by the change in the aperture value, and data Avs for calculating the set aperture value from the register REG ₁₀ in FIG. 3
6 is a data output device that outputs data Tvs of the set exposure time, and this data Tvs is also sent to the exposure calculation circuit 40.
is input. Reference numeral 38 denotes a mode setting device; 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. Aperture priority exposure time automatic control mode (hereinafter referred to as A priority mode) in which terminal T becomes "High" and exposure time is automatically controlled according to the set aperture value, film sensitivity value, and subject brightness.
In this case, terminal A becomes "High", and 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 becomes "High". In the manual control mode (hereinafter referred to as M mode) in which both the exposure time and the aperture are controlled by manual setting values, the terminal M becomes "High".
These terminals T, A, P, M are connected to the exposure calculation circuit 40.
The exposure calculation circuit 40 calculates the mode corresponding to the mode designation signal from one of the terminals T, A, P, and M, and outputs data for controlling and displaying the exposure time to the output terminal OUT ₃ . and a multiplexer 42 to an exposure time control device 50 and an exposure time display device 52, data for aperture control is transmitted from an output end OUT ₁ to an aperture control device 54, and data for aperture display is transmitted from an output end OUT ₂ to an aperture display device 56. Output to each. 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 maximum aperture value Avo+k is determined based on the change in aperture value caused by attaching the lens adapter, and the limited aperture value Avc is determined by attaching the lens adapter.
If Avo+k>Avc, the process moves to step #2, and if Avo+kAvc, the process moves to step #38. When moving to step #2, the data input from the addition circuit 26 to the exposure calculation circuit 40 is Ev-(Avo+k),
In step #2, the calculation Ev-(Avo+k)+(Avo+k)=Ev is performed, and an exposure value Ev that is not affected by the open aperture value is calculated. In the following step #3, the mode is determined based on the mode designation signal of any terminal T, A, P, or M given from the mode setting device 38, and if it is the T priority mode, the process goes to step #4, and the mode is changed to the A priority mode. If so, go to step #14, if it is P mode, go to step #24, and if it is M mode, go to step #34. First, the case of the T priority mode from step #4 will be explained. In step #4, calculate Ev-Tvs=Ave, then calculate the effective aperture value Ave and Avo.
+k and Avmax+k. Here, if Avo+kAveAvmax+k, it means that control to this effective aperture value Ave is possible.In step #6, the number of aperture stages, that is, (Ave-k)-Avo is calculated, and the output is Output the data for this number of refinement stages to the terminal OUT ₁ . This data is input to the aperture control device 54. 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. In addition, the effective aperture value data Ave calculated in step #4 is output to the output terminal OUT ₂ in step #7, and the aperture display device 5
This effective aperture value is displayed at 6. In step #8, the set exposure time data Tvs is sent to the output terminal.
Output to OUT ₃ . Then, the process returns to step #1 again 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 Avo
The data is set as the set aperture value data Avs and the mode is shifted to the A priority mode starting from #14. Also, if it is determined in step #5 that Ave>Avmax+k, it is impossible to control the aperture as described above, so Avmax is set as the set aperture value and the mode shifts to the A priority mode. In addition, Ave<Avo+k or Ave>Avmax+k
The newly set Avo or
Exposure time determined based on Avmax Tv=
If the exposure time is outside the range of exposure time that can be controlled by Tv min (maximum exposure time) or Tv=Tvmax (minimum exposure time), it will be impossible to take pictures with proper exposure. In these cases, the exposure is controlled by setting the effective aperture value to Avo+k and the exposure register to Tvmin, and also performs an under warning or setting the effective aperture value to Avmax.
+k, it is desirable to perform exposure control by setting the exposure time to Tvmax 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 mentioned above, Avs + k is the effective aperture value when the lens aperture value is controlled to Avs.
It is Ave. Next, the calculated exposure time data
Determine whether Tv is within a controllable range. If Tv minTvTvmax, data on the number of aperture stages of Avs-Avo is sent from the output terminal OUT ₁ to the aperture control device 54, and data on the effective aperture value of Avs+k is sent to the output terminal OUT. ₂ to the aperture display device 56, the exposure time data Tv is output to the aperture display device 56.
The output is output from OUT ₃ to the exposure time control device 50 and the exposure time display device 52, and the process returns to step #1.
When it is determined in step #15 that Tv<Tvmin, Tvmin is set as the exposure time and the mode shifts to the priority mode from step #4. At this time, if Avs = Avo, it is impossible to control the appropriate exposure, so an under warning is performed and Avo and Tvmin
It is desirable to perform control based on On the other hand, if it is determined that Tv>Tvmax, Tvmax is set as the set value and the mode shifts to T priority mode. In this case as well, if it is determined that Avs=Avmax, it is desirable to issue an over warning and control the exposure based on Avmax and Tvmax. Next, the P mode starting from #24 will be explained. First, in step #24, p.Ev=Ave (0<p<1) Ev-Ave=Tv is calculated, and then it is determined whether Ave is within a controllable range. If Avo+kAveAvmax+k, then the data of the number of refinement stages of (Ave-k)-Avo is output to the output terminal _OUT1 . This data is the number of stops of the aperture on the lens side to achieve the calculated effective aperture value Ave, as in the case of the T priority mode. And then,
The effective aperture value data Ave is output to the output terminal OUT ₂ , the calculated exposure time data is output to the output terminal OUT ₃ , and the process returns to step #1. Also, if Ave<Avo+k, step #30 uses Avo as the set aperture value data and returns to the A priority mode from #14; conversely, if Ave>Avmax+k, step #32 Then, use Avmax as the set aperture value data and shift to A priority mode from #14. Next, in the case of M mode, the output end OUT ₁ contains data Avs of the number of aperture stages based on the set aperture value Avs.
−Avo is effective aperture value Avs+k for output end OUT ₂
But the output terminal OUT ₃ has the set exposure time data Tvs
are output, and the process returns to step #1. Now, if it is determined in step #1 that Avo+kAvc, then the data input from the adder circuit 26 to the arithmetic circuit 40 is Ev
-Avc, the calculation of (Ev - Avc) + Avc = Ev is performed in step #38, and in step #39, the exposure control mode is determined and the sixth
Shift to the calculation flow for each mode in Figure 2. In FIG. 6-2, in the T priority mode, first, in step #40, Ev-Tvs=Ave is calculated, and then it is determined whether Ave is within a controllable range. At this time, if AvcAvcAvmax+k, then (Ave-k)-Avo, Ave, Tve as in the case of T priority mode in Figure 6-1.
The data of output terminals OUT ₁ , OUT ₂ ,
Output to OUT ₃ and return to step #1. Further, if Ave<Ave, Avc-k is set as the aperture value and the flow shifts to the A priority mode from #61. At this time, if Tvs = Tvmin, proper exposure is impossible, so an under warning is performed and Avc-k,
It is desirable to perform exposure control using Tvmin as a set value. On the other hand, if Ave>Avmax+k, the flow shifts to A priority flow from #51 with Avmax as the set aperture value, but in this case as well,
If Tvs = Tvmax, issue an over warning,
It is desirable to perform exposure control using Avmax and Tvmax as set values. Next, the operation in the A priority mode from step #50 will be explained. First, when it is determined in step #50 that Avs+kAvc, Ev-(Avs,k)=Tv is calculated, and then it is determined whether Tv is within a controllable range. At this time, if TvminTvTvmax, the data of Avs-Avo+Avs+k and Tv are output to the output terminals _OUT1 , _OUT2 , and _OUT3, respectively, and the process returns to step #1. Also, if Tv<Tvmin, Tvmin is set as the set exposure time and the flow shifts to the T priority mode from #40.On the other hand, if Tv>Tvmax, Tvmax is set as the set exposure time and T priority mode flow starts from #40.
Transition to priority mode flow. At this time, if Avs=Avmax, it is desirable to issue an over warning and perform exposure control using Avmax and Tvmax. If it is determined in step #50 that Avs+k<Avc, the process moves to steps #61 and subsequent steps. In this case, the effective aperture value based on the aperture setting of the lens aperture is on the open side than the limited aperture value due to the attachment of the lens adapter, so the actual effective aperture value is Avc. At this time
Avc is reset as the effective aperture value, Ev-Avc=Tv is calculated, and it is determined whether the problem is that Tv can be controlled. If TvminTvTvmax, move to step #64, output end OUT ₁ will have data with the number of stop stops being 0, output end OUT ₂ will have data with effective aperture value Avc, and
Exposure time data Tv is output to OUT ₃ , and the process returns to step #1. In addition, when it is determined that Tv<Tvmin, the set effective aperture value is the widest aperture value Avc, so proper exposure is impossible, and in this case, Tvmin
As the calculated value, proceed to step #64 below. Note that at this time, it is desirable to also issue an under warning. On the other hand, if Tv>Tvmax, Tvmax is set as the set value and the flow shifts to the T priority mode. In the case of P mode, the calculation p·Ev=Ave Ev−Ave=Tv is performed in step #70, and the following operations are the same as in the case of TT priority mode from #41. In the case of M mode, if it is determined that Avs + kAve at step #80, the process moves to steps #81 and below and the number of aperture stages Avs - Avo and the effective aperture value are determined.
Output terminals for Avs+k and exposure time Tvs data respectively
Output to OUT ₁ , OUT ₂ , and OUT ₃ and return to step #1. On the other hand, if it is determined at step #80 that Avs+k<Avc, the process moves to step #85, where the number of aperture stages is 0, the effective aperture value Avc,
The exposure time Tvs is output from the output terminals OUT ₁ , OUT ₂ , and OUT ₃ , and the process returns to step #1. Note that when only the interchangeable lens is attached, the output of register REG ₃ in Figure 1 is “00000”.
The photometric data is Bv-Avo. In this case, from the decoders 30 and 32, Avc=0, k=
If 0 data is output, normal exposure calculation will be performed according to the aforementioned flow (Fig. 6-1). The remaining portions of FIG. 5 will be explained again. The decoder 44 determines whether the lens adapter is equipped with an automatic aperture mechanism or not based on the lens adapter type data from the register REG ₃ .
As shown in Table 3, when data "01001", "01010", "01011", and "01100" indicating that the accessory is not equipped with an automatic aperture mechanism are input, the output of the decoder 44 becomes "High". become,
When any other data is input, it becomes “Low”. In addition, when the lens is attached and the check code "11100" data is not input to the register REG ₄ in FIG. 1, the output of the AND circuit AN ₁₆ becomes "Low" and as shown in FIG. The input level to the OR circuit 46 becomes "High".
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 is "High".
become. At this time, since there is no need to control the aperture, this output is given to the aperture control device 54, and the control device 54 becomes inactive. In addition, since the aperture display does not need to be displayed except when displaying the set aperture value, the OR circuit 6 is
0 and the output of the OR circuit 46,
The output of the AND circuit 62 becomes "High" and the aperture display in the aperture display device 56 is made inactive. Next, regarding the exposure time, if 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 "Low"), A “High” signal is output from the AND circuit 48. This signal is sent to the selection terminal SE of the multiplexer 42,
In this case, the Ev-Avn data from the adder circuit 26 based on the photometry of the subject that has passed through the manually aperture of the lens, that is, the aperture photometry, is output as is. This data is then displayed as a proper exposure time on the display device 52, and the exposure time is further controlled by the exposure time control device 50 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", in the M mode (terminal M is "High"), the output of the AND circuit 48 is "Low", and the output from the multiplexer 42 is output from the exposure calculation circuit 40. The data of the set exposure time Tvs is output as is, and display control is performed based on the data Tvs. Moreover, if the output of the OR circuit 46 is “Low”,
Display control is performed based on data from the exposure calculation circuit 40. In zoom lenses with variable focal lengths, at least three representative focal lengths are displayed on the setting member for focal length adjustment, and it is possible to infer the set focal length to a certain extent, but It is impossible to determine at a glance the value of a specific focal length or the extent to which the set focal length falls within the adjustable focal length range.
An embodiment in which the above information regarding the set focal length is made visible within the viewfinder of the camera will be described below. Here, we will explain the display based on the data that indicates the minimum focal length, maximum focal length, set focal length, and percentage of the set focal length read into registers REG ₇ , REG ₈ , REG ₁₁ , and REG ₁₃ in Figure 1. explain. 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】

【table】

[Table] 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 set focus input to each zoom lens. It indicates distance. 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 longer than that shown in Table 5. It is also possible to create data that is finely divided. 10・log ₂ column is each setting focal length f10・log ₂ f
The difference column shows the shortest focal length.
When fmin is set, it shows the value of 10・log ₂ f−10・log ₂ fmin, and the display data column is “00001” if the value of f−f min/f max−f min×100 is 0 to 19, and “00001” if the value is 20 to 39 is "00010", 40-59 is "00100", 60-79 is "01000", and 80-100 is "10000". In order to obtain these various data in more finely divided form, 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 (for the attached lens). identification data) and setting data (third
Based on the data from block 12 in the figure, the set focal length, 10·log ₂ , difference data, and display data may be obtained. In Fig. 7, the data on the shortest focal length from the register REG ₇ is converted into display data by the decoder DE ₁₀ and sent to the display device DP ₁ , where the shortest focal length is displayed numerically as shown in Fig. 8. Ru. The longest focal length data from the register REG ₈ is converted into display data by the decoder DE ₁₁ , and the longest focal length is displayed numerically on the display device DP ₂ as shown in FIG. Further, _the set focal length data from the register REG ₁₁ is converted into display data by the decoder DE ₁₂ and sent to the display device DP ₃ , where it is displayed numerically as shown in FIG. Further, the % data from the register REG ₁₃ is sent to the display device DP ₄ and displayed on one of the display sections e ₁ to _{e 5} . That is, e ₁ for “00001”, e ₂ for “00010”,
e ₃ for “00100”, e _{4 for “01000”, e 4} for “10000”
e ₅ will be displayed to show what percentage of the overall performance the set focal length is. Note that 60 indicates the field of view within the finder. FIG. 9 is a block diagram showing a second example for displaying the set focal length in the viewfinder, and FIG. 10 shows an example of the display section. Decoders DE ₁₅ and DE ₁₆ are decoders that convert the maximum focal length fmax and set focal length f data from registers REG ₈ and REG _11, respectively, into data of 10·log ₂ fmax and 10·log ₂ f. one decoder DE ₁₅ ,
The data from DE ₁₆ is input to the subtraction circuit 70.
Data of 10・log ₂ (fmax/f) is output. This data is input to the decoder 72 and sent to one of the terminals f ₀ corresponding to the decoder from the subtraction circuit 70.
~ _f24 becomes “High”. That is, if the data from the subtraction circuit 70 is 24, the terminal f ₂₄ is input, and if the data is 23, the terminal f ₂₃ is input.
Similarly, if the data is 1, the terminal f ₁ is used, and if the data is 0, the terminal
f ₀ becomes “High”. And terminals f ₂₄ - f ₂₂ are connected through diodes to terminal g ₁ , terminals f ₂₁ - _{f 19}
through a diode to terminal g ₂ , terminals f ₁₈ to f ₁₃ to terminal g ₃ through a diode, f ₁₂ to f ₆ to g ₄ , f ₅
~f ₀ are connected to g ₁ , respectively. The display device 74 displays a display line provided within the viewfinder visual field ₆₀ in _FIG.
One of h ₁ , h ₂ , h ₃ , and h ₄ will be displayed. Display lines h ₁ to _{h 4} in Figure 10 indicate the field frame visible within the viewfinder field of view when the set focal length is set to the maximum focal length. For example, if the set focal length is 500 to 360 mm, terminal g ₄ will be set to "High" and no line will be displayed;
At ~250mm, terminal g ₄ becomes “High” and line h ₄
is displayed, and terminal s ₃ is “High” at 200 to 180 mm.
, line h ₃ is displayed, and at 135 to 120 mm, terminal g ₂ becomes “High” and line h ₂ is displayed,
If it is less than 120mm, terminal g ₁ becomes “High” and the line
h ₁ 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 the shortest focal length, longest focal length, and set focal length are numerically displayed on the display units DP ₁ , DP ₂ , and DP ₃ as in the first example. In addition, the shift register SR ₂ in FIGS. 2 and 3,
As for the configuration of SR ₃ , the data of ROM, RO ₁ , and RO ₂ are taken in parallel at the timing when TA ₇ and TL ₇ are “High”, and the data is transferred to 1 from the next rising timing of TA ₀ and TL ₀ . Although it is assumed that bits are sequentially output to the camera body side, the specific configuration of this shift register is as follows. That is, a flip-flop is provided for each bit in which the data of each bit input in parallel is preset.
The output terminal of the flip-flop corresponding to the lower bit is connected to the input terminal of the flip-flop corresponding to the bit immediately above the lower bit, and the data preset in each flip-flop is transferred to the lower bit in synchronization with the clock pulse. The bits are transferred sequentially from bit to upper bit. Furthermore, these flip-flops
If another flip-flop is provided in addition to the flip-flop, and the input terminal of this flip-flop is connected to the output terminal of the flip-flop corresponding to the most significant bit, only one clock pulse will be output from this separate flip-flop. After a delay, the captured data is output bit by bit. In the above explanation, the reading start signal (start) is output from flip-flop FF ₁ by closing photometric switch S ₁ , but instead of outputting it through flip-flop FF ₁ like this, , the power line (+V) generated by closing the photometric switch S ₁ is read and used as a start signal (start), and this voltage signal is applied to the connection terminal JB _3.
The information may also be transmitted to the accessory via the . Note that the timing at which the reading start signal (start) is generated is not limited to when the photometry switch _S1 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 was configured with a logic circuit for convenience of explanation, but this could 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, it's a good thing. [Effects of the Invention] As explained above, according to the present invention, the reading means includes a first data storage area that stores a first data group common to the first type of lens and the second type of lens. and a second data storage area that stores a second data group specific to the first type of lens, and if the interchangeable lens attached to the camera is the first type of lens, the second data storage area stores the second data group specific to the first type of lens. A reading operation is executed to read the first and second data groups and store them in the first and second data storage areas, and if the attached interchangeable lens is the second type of lens, the first data group is read. A read operation is performed to read only the group and store it in the first data storage area. As a result, if the interchangeable lens attached to the camera is the second type of lens, in order to match the number of data types with the first type of lens, the second data group may be meaningless or the camera side Even if the control system stores data that is not used,
Since such meaningless or unused data is not read, information processing within the camera system can be speeded up.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the camera body side in the present invention, FIGS. 2 and 3 are circuit diagrams showing an embodiment of the accessory side, respectively, and FIG.
The figure shows the specific circuit configuration of the setting device.
The figure is a block diagram showing the configuration of the exposure control section on the camera body side to which the present invention is applied, Figures 6-1 and 6-2 are flowcharts thereof, and Figure 7 is another example of application of the present invention. 8 is a block diagram showing an example of the display, and FIG. 9 is a block diagram showing another embodiment of the camera shown in FIG. 7. 10 are diagrams showing examples of the display. RO ₁ , RO ₂ ...Fixed memory circuit, CO ₄ , CO ₆ ,
CO ₇ , DE ₃ , DE ₄ , MP ₁ , MP ₂ ...addressing device, SR ₂ , SR ₃ , AS ₁ , AS ₂ ... information transmission device,
SR ₁ , REG ₁ ~ REG ₁₃ ... Information reading device, s ₁ ,
BT ₁ , 1... Read signal generation circuit, 10, 1
1, 12...Setting device, VT...Sliding member, PA ₀
~ _PA3 , _IN20 ~ _IN23 , _EO0 ~ _EO2 ...Signal output members.

Claims (1)

[Claims] 1. A first type of lens in which a first data group and a second data group unique to an interchangeable lens are stored, and a second type of lens in which only the first data group is stored. an interchangeable lens camera system that is selectively attached to a camera body, comprising: a first data storage area for storing the first data group; and a second data storage area for storing the second data group; The first data group is read from the interchangeable lens based on the clock signal.
and a reading means for storing data in a second data storage area; a determining means for determining whether the interchangeable lens attached to the camera body is a first type of lens or a second type of lens; When it is determined that one type of lens is attached, the first and second data groups are read from the interchangeable lens and the first and second data groups are read from the interchangeable lens.
and when it is determined that the second type of lens is attached, read only the first data group from the interchangeable lens and store it in the first data storage area. What is claimed is: 1. A camera system with interchangeable lenses, comprising: reading control means for controlling the means; 2. The interchangeable lens camera system according to claim 1, wherein the first type of lens is a variable focal length lens and the second type of lens is a fixed focal length lens.