In a curtain lock two blinds made of cloth located just before a personnel window of the device along the shot plane. At a of a lock of a blind along or across a personnel window one by one; width between blinds of a crack can. Than the speed of a of blinds and than less width of a crack is more. the less endurance. Thus, if in the central lock light beams arrive to all points of a shot, in a lock the photosensitive layer consistently, a site behind a site, that is various sites of a photosensitive layer are exhibited at different times. If of both blinds are not identical, it results in unevenness of endurance with which various sites of a shot that reduces quality of the received picture. In some cameras the fan lock is used. which is a kind of a curtain lock. For automation of processing various on duration locks of cameras equip or mechanical perylyatorami of endurance (usually — brake mechanisms anchor type, or electronic actuation devices.
The photographic materials used in the photo have a certain sensitivity to light. The main components of any photographic material are a basis ( and a photosensitive layer, on it. On a basis photographic materials are subdivided into photographic plates, a photo and films and photographic papers. A basis at photographic plates glass, at photo films — from special grades of a or lavsan, and at photographic papers — from dense paper or a cardboard.
The lightproof chamber, at the same time is the case of a. In a camera knots and mechanisms of the camera are mounted, and their governing bodies are outside located. The camera has a nest for accession of a lens. At low-format cameras of a has a back folding cover. In part of a camera the carving nest for installation of the camera on a support is made.
The relative opening of an — the relation of diameter of its entrance to focal length, registers in the form of 1:K where To — diaphragm number,, in how many times the focal length of an is more than diameter of its entrance pupil. It , called by diaphragm number, is applied on a scale of diaphragms of a lens. The more the of a relative opening, the is higher an of the optical image given y, i.e. the it is more than svetosil of a lens.
The most important parts of all devices are the camera, a lens, the device for a lens, the view-finder, a lock in the mechanism. Poly perfect are equipped with in addition exponometrichesky device or built in, sinkhrokontakty, automatic release and adaptations.
The focal length (f') determines the size of the image given by a lens, i.e. its scale or linear increase. The more the focal length, the is more scale than the chayemy image at same a to the photographed subject. The majority of photolenses has a constant focal which size is specified by a pas to their frame. Some cameras have lenses with variable focal length which can be changed smoothly in certain limits. Photolenses at which the focal length is approximately equal to a diagonal of a personnel frame of a (1k), it is accepted to call normal. If f exceeds 1k, such lenses by the dlinnofokusny; some lenses are called telephoto lenses. Lenses which focal length is less than lk, are called short-focus.
Often instead of a plano-convex lens Fresnel's lens containing some zones operating as a convex of a usual lens. This lens is made of glass that considerably reduces its weight. The Klinovy device at such lens is replaced with system of the smallest pyramids (microfeasts, called by a microraster. At supervision through a microraster the slightest inaccuracy in focusing of a lens is shown in a of the unsharpness of the image, more noticeable, than it a matirovanny surface.
Resolving power (ability) of L' is expressed by the maximum number of (a stroke, falling on 1 mm in the optical image of a special test (worlds). The resolution of a lens is higher, the bigger number of fine details by a lens separately.