Search results
Results from the WOW.Com Content Network
The small exit pupil of a 25×30 telescope and large exit pupils of 9×63 binoculars suitable for use in low light. For a telescope, the diameter of the exit pupil can be calculated by dividing the focal length of the eyepiece by the focal ratio (f-number) of the telescope. In all but the cheapest telescopes, the eyepieces are interchangeable ...
Typical eye relief distances for telescopic sights are often between one and four inches (25 to 100 mm), as opposed to the much shorter 15 to 17 mm for typical binoculars. The exit pupil widths in rifle sights are designed to be larger than the eye's pupil, to allow for a range of motion without vignetting.
Exit pupil – Telescopic sights concentrate the light gathered by the objective into a beam, the exit pupil, whose diameter is the objective diameter divided by the magnifying power. For maximum effective light-gathering and brightest image, the exit pupil should equal the diameter of the fully dilated iris – for a youthful dark-adapted ...
The entrance pupil made by a single lens with an aperture (aperture stop) behind it. The entrance pupil is the image of the aperture stop viewed from the front of the optical system and here it is a virtual image. Chief rays and marginal rays determine the location and the size of the entrance pupil, respectively.
C79 Reticle as shown in the declassified danish manual of arms HRN 111-00 for the M95 family of rifles (C7,C8 and C8IUR) The reticle of the C79 sight was designed to serve on the C9 Light Machine Gun, thus an appropriate pattern was chosen to aid the gunner in judging distance.
Eye relief: For optics such as binoculars or a rifle scope, eye relief is the distance from the eyepiece to the viewer's eye that matches the eyepiece exit pupil to the eye's entrance pupil. Short eye relief requires the observer to press their eye close to the eyepiece in order to see an un-vignetted image.
The exit pupil is located at infinity, and chief rays after the objective are parallel to the optical axis. An image-space telecentric lens has the exit pupil (the image of the aperture stop formed by optics after it) at infinity and produces images of the same size regardless of the distance between the lens and the film or image sensor. This ...
The PSO-1 elevation turret features bullet drop compensation (BDC) in 50 metres (55 yd) or 100 metres (109 yd) increments for engaging point and area targets at ranges from 100 metres (109 yd) up to 1,000 metres (1,094 yd).