Abstract: There is described a camera incorporating a focal-plane shutter. The camera includes a lens, an image window having an aperture to bound a light coming through the lens in a plain perpendicular to an optical axis of the lens, a focal-plane shutter and a photometry sensor to receive the light reflected by the focal-plain shutter and detect an amount of the light reflected by the focal-plane shutter after coming through the lens. In the camera, the photometry sensor is located at an outside of the aperture and resides on a plane, which is parallel with the optical axis and includes a line which is parallel to a long-axis of the aperture and passes substantially a center of a short-axis of the aperture.

Abstract: A single-lens reflex camera comprises a quick return mirror which can be positioned at an object observing position (or an inclined position) and a photographing position (or a horizontal position). A photoreceptor element is disposed in such a manner that a light receiving surface of the photoreceptor element faces a shutter, so that a light beam reflected by the shutter is led to the photoreceptor element. When the quick return mirror is retreated to the photographing position, the light beam is received by the photoreceptor element. When a change in the amount of received light by the photoreceptor element exceeds a predetermined range while the mirror is retreated to the photographing position before the shutter release operation, a warning is output.

Abstract: An exposure control apparatus for an electronic development type camera having a photographic optical system. The camera uses a recording medium in which subject images formed through the photographic optical system are electrically developed. The exposure control apparatus includes a detecting device for detecting first photometric data which corresponds to subject light passed through the recording medium at a moment an exposure of the recording medium commences. The detecting device further detects second photometric data which corresponds to subject light passed through the recording medium after the exposure commences and before the exposure terminates. The exposure control apparatus further includes a calculating device for calculating a transmittance of the recording medium after the exposure commences, using the first and second photometric data, and a controlling device for controlling the exposure of the recording medium in accordance with the calculated transmittance.

Abstract: A camera which prevents accidents which could lead to damage to the shutter when performing shutter time tests in the opened state of the back cover of a camera. The camera has a shutter to limit the exposure time of the recording medium which has been loaded, a measurement unit to measure, according to the action of the shutter, the time of the exposure to the recording medium which the shutter performs, and a back cover sensor to detect whether the back cover is open or closed when film or another recording medium has been loaded into the camera. The action of the measurement unit is inhibited when the back cover sensor detects that the back cover is open. The camera also has a drive unit for recording an image on the film or recording medium and a mode selection switch to select between a normal mode in which a photographic action is performed, in which the shutter and the drive unit are activated, and a test mode in which the shutter and the measurement unit are activated but not the drive unit.

Abstract: A camera which can detect the actual opening/closing state of the camera shutter based on a signal reflected towards the shutter by a signal projection unit and received by a signal receiving unit. The signal received by the signal receiving unit is based on the reflectivity of the shutter and, therefore, the signal received by the signal receiving unit is different depending on whether or not the shutter is open or closed. The camera has a reflectivity state detection unit for determining the reflectivity status of the shutter. A reflectivity standard changing unit changes the detection standard of the signal receiving unit based on information output by the reflectivity state detection unit. In this manner, changes in reflectivity of the shutter, due to passage of time or increase in use, will not reduce the accuracy of the detection of the open/close status of the shutter.

Abstract: A photometric device, to measure light incident from a photographic lens of a camera, which can perform accurate photometry, independently of the direction of polarization of the incident light. The photometric device is provided with a first semi-transparent mirror, located between the photographic lens and an imaging plane of the camera, for dividing incident light from the photographic lens into a reflected beam and a transmitted beam. A second semi-transparent mirror is located in a position where the reflected beam from this first semi-transparent mirror is incident, and divides the incident light into a reflected beam and a transmitted beam. A photometric unit, for performing photometry, is located in a position to receive light of the transmitted beam from the second semi-transparent mirror.

Abstract: An automatic exposure device in a camera divides an object field into a plurality of areas and photometers them by the use of a divisional photometry element, and calculates optimum exposure from the result of the photometry. The divisional photometry element includes a photometric converting portion for photoelectrically converting incident light in each of the areas and putting out an output, and a reading portion for reading out the plurality of outputs of the photoelectric converting portion. When the number of successive outputs of a row of the areas in the readout direction which exceed a predetermined value is greater than a predetermined number, the output of that row is completely omitted in the calculation of the optimum exposure.

Abstract: A camera shutter control device includes a controller for controlling the camera, a shutter device having front and rear curtains, and shutter drives for driving the curtains. A computation device determines the shutter time and a correction device corrects the shutter time based on correction values stored in a memory. The shutter curtains are continuously controlled by the controller based on a corrected shutter time, wherein the corrected shutter time can have either a positive, negative, or zero value.

Abstract: An automatic light modulating camera effecting a preliminary light emission and a main light emission, extracts effective light metering areas from plural light metering areas based on the light metering signals obtained at the preliminary light emission and on lens signals indicating the states of a phototaking lens at the preliminary light emission, and terminates the main light emission based on the light metering signals obtained in the effective light metering areas.