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Eye care professionals use prism correction as a component of some eyeglass prescriptions. A lens which includes some amount of prism correction will displace the viewed image horizontally, vertically, or a combination of both directions. The most common application for this is the treatment of strabismus. By moving the image in front of the deviated eye, double vision can be avoided and ...
The prism cover test ( PCT) is an objective measurement and the gold standard in measuring strabismus, i.e. ocular misalignment, or a deviation of the eye. [1] It is used by ophthalmologists and orthoptists in order to measure the vertical and horizontal deviation and includes both manifest and latent components. [1]
The Nikon F2 is an all-metal, mechanically-controlled (springs, gears, levers), manual focus SLR with manual exposure control. The camera itself needed no batteries, though the prism light meter did (and the motor drive if added). The F2 replaced the Nikon F, adding many new features (a faster 1/2000-second maximum shutter speed, a swing open ...
The Eye-Level and AE Finders are the basic eye-level prism finders, similar to most other SLR systems' prism finders. Both include a hot shoe for on-camera flash, or attachments to remotely trigger the shutter. Both also include an integral eyepiece shutter, which closes over the eyepiece to prevent light leakage during long exposures.
The Canon AE-1 is a 35 mm single-lens reflex (SLR) film camera for use with interchangeable lenses. It was manufactured by Canon Camera K. K. (today Canon Incorporated) in Japan from April 1976 to 1984. It uses an electronically controlled, electromagnet horizontal cloth focal plane shutter, with a speed range of 2 to 1/1000 second plus Bulb and flash X-sync of 1/60 second. The camera body is ...
Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes ( binocular vision) when viewing distant objects. Most binoculars are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal -mounted military models.
The Canon FD lens mount is a physical standard for connecting a photographic lens to a 35mm single-lens reflex camera body. The standard was developed by Canon of Japan and was introduced in March 1971 with the Canon F-1 camera. It served as the Canon SLR interchangeable lens mounting system until the 1987 introduction of the Canon EOS series ...
Eye glasses with an included prism power is the optical method to reduce a fixation disparity. Different procedures have been proposed to determine the required amount of prism for the individual.
The Nikon F3 was Nikon 's third professional single-lens reflex camera body, preceded by the F and F2. Introduced in March 1980, it had manual and semi-automatic exposure control whereby the camera would select the correct shutter speed (aperture priority automation). The Nikon F3 series cameras had the most model variations of any Nikon F camera.
In optics, chromatic aberration ( CA ), also called chromatic distortion and spherochromatism, is a failure of a lens to focus all colors to the same point. [1] It is caused by dispersion: the refractive index of the lens elements varies with the wavelength of light. The refractive index of most transparent materials decreases with increasing wavelength. [2] Since the focal length of a lens ...