Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data is transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data is transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data is transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: A camera comprising a flash unit attachable to a camera body, a switching device and a control device. The flash unit includes a light emitter switchable between an emission permit state in which the light emitter is projected from a body of the flash device and an emission prohibit state in which the light emitter is retracted into the body. The flash unit further includes a control circuit for selectively placing the light emitter in the emission permit state and the emission prohibit state. A main switch is provided in the camera body to be switchable between a position for permitting a camera operation and a position for prohibiting the camera operation. When the light emitter is placed in the emission permit state when the main switch is switched to the position for permitting the camera operation.

Abstract: A camera comprising a flash unit attachable to a camera body, a switching device and a control device. The flash unit includes a light emitter switchable between an emission permit state in which the light emitter is projected from a body of the flash device and an emission prohibit state in which the light emitter is retracted into the body. The flash unit further includes a control circuit for selectively placing the light emitter in the emission permit state and the emission prohibit state. A main switch is provided in the camera body to be switchable between a position for permitting a camera operation and a position for prohibiting the camera operation. When the light emitter is placed in the emission permit state when the main switch is switched to the position for permitting the camera operation.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in a plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data transmission between the microcomputer and the circuits uses a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer, are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit. The camera system is capable of coordinating flash mode and a bracket exposure mode.

Abstract: From a data transmission device to a camera system including a camera and electronic flash device, operation instruction data such as set or calculated exposure control data, shutter release data instructing the operation of the camera system, flash emission testing data and the like are serially transmitted in the form of infrared light signal. When the reception of these data is completed, the camera starts its operation to control given operation of the camera system such as the exposure initiation of the camera, test light emission of the electronic flash device and the like in accordance with received data.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data is transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: From a data transmission device to a camera system including a camera and electronic flash device, operation instruction data such as set or calculated exposure control data, shutter release data instructing the operation of the camera system, flash emission testing data and the like are serially transmitted in the form of infrared light signal. When the reception of these data is completed, the camera starts its operation to control given operation of the camera system such as the exposure initiation of the camera, test light emission of the electronic flash device and the like in accordance with received data.

Abstract: A camera system including a camera body and a camera accessory attachable to the camera body, such as an interchangeable back lid, an interchangeable lens, a flash device and so on, is disclosed. In the system, a plurality of circuits provided in the plurality of camera accessories are controlled by a microcomputer provided in the camera body. Data is transmitted between the microcomputer and the circuits using a serial data bus and synchronizing clock line connected therebetween. The circuit to receive the data sent from the microcomputer, or the circuit which should send the data to the microcomputer are selected by the microcomputer through chip select lines provided between the microcomputer and each circuit.

Abstract: A photographic camera provided with a focus detecting system having a device for periodically sensing a focus condition of the camera to repeatedly produce a signal in response to every periodical sensing of the focus condition so as to effect the focus detection according to the signal from the sensing device.

Abstract: A camera acoustic indicating device for indicating, by sound, attainment of an in-focus condition of a camera objective lens and warning possibility of a blur occuring exposure time due to low brightness of an object to be photographed. The sound for the in-focus indication is intermittently generated at a frequency higher than that at which the sound for the blur warning is intermittently generated. When the attainment of an in-focus condition is detected while the blur warning is being made, the warning is interrupted for a given time period during which the attainment of the in-focus condition is indicated for a short time.

Abstract: An exposure time control device for a camera which measures the light reflected from a surface of a leading shutter curtain and/or a surface of a film can determine exact exposure time even if difference exists between reflection factors of the surfaces, by means of a simple construction including no special light measuring circuit other than a light measuring circuit originally provided for the exposure time control purpose. A first memory or storage capacitor memorizes logarithmically compressed output of the light measuring circuit fed through a first switch when the first switch is opened in conjunction with start of the leading shutter curtain travel while a second storage or memory capacitor memorizes the output fed through a second switch when the second switch is opened in conjunction with completion of the leading shutter curtain travel.

Abstract: In a camera shutter control system, film exposure is ensured even when object brightness is so high as to require a shutter speed faster than the maximum shutter speed available and at which shutter operation might not cause film exposure without the present invention. A delay circuit provides a delay in addition to the time provided by the shutter control circuit as a function of object brightness, and a delay control circuit actuates the delay circuit only when the object brightness exceeds a given level. An optional flash control circuit interrupts flash firing in response to the shutter closing signal of the shutter control system. In that case, the delay control circuit is disabled in response to the high brightness of the object illuminated by the flash light, by means of a low pass filter which does not allow the rapidly changing signal produced by the flash to be transmitted to the delay control circuit.

Abstract: An exposure time control system includes a circuit which denergizes a shutter control circuit and an electromagnet and causes a shutter closure when an electronic flash device is triggered to fire an electronic flash tube. The system further includes a power supply circuit and a self-maintaining circuit for maintaining the power supply circuit at its active condition after it is activated even after a power switch therefor is opened. A signal generated upon the trigger of the flash device releases the self-maintenance of the power supply.

Abstract: An indicating system for use in a photographic camera of the type having a focal plane shutter and permitting flash firing only when the shutter speed is longer than a given value to ensure the full uncovering of the film surface upon flash firing. The indicating system normally indicates an exposure time to be effected in accordance with the object brightness. When the indicated prospective exposure time is longer than the given value, an indication member of the system provides a different indication than the normal exposure time indication. The indicating system includes a plurality of light emitting diodes (LEDs) of the same number corresponding to that of the exposure times to be indicated, with the LEDs being selectively energized continuously to indicate a respective exposure time.

Abstract: An exposure meter for use in photography which includes means for measuring brightness at a plurality of places in a scene to be measured for exposure, means for calculating frequency distribution of the brightness which divides brightness value into many stages and counts frequency of occurrence of brightness at each of the stages, and means for calculating, under designated conditions, position whereat film latitude is to be present within the width of the brightness distribution.

Abstract: An exposure meter provides a display indicating the brightness of selected portions of a scene to be photographed. In one embodiment, a photometering block including a plurality of light sensitive elements is employed, and there is an automatic fixed display indicating the brightness level of the brightest and the darkest portions of the objective scene together with a display of a median value. Another embodiment employs a spot photometering device with only one light sensitive element, and a display of the brightness level of different portions of the scene selected by the photographer.

Abstract: A light responsive circuit adapted to measure natural or ambient light and artificial light such as from an electronic flash device, includes a photocell, a logarithmic compression circuit for generating a first output proportional to the logarithm of the light intensity incident on the photocell, a calculation circuit for adding to or subtracting from the first output an electric quantity, such as voltage, which is determined in accordance with a light unrelated input, for example, a film sensitivity setting, thereby generating a second output as a result of the addition or subtraction, a logarithmic expansion circuit for generating a third output proportional to the anti-logarithm of the second output, and an operating circuit responsive to the third output for controlling or indicating at least one camera exposure factor.