Process lens
A lens system designed specifically for high quality copying.
Search SWPP and BPPA
Information provided by: SWPP BPPA
More Photographic Terms ...
process lens
a lens having a long focal length, corrected for flat copy and used in a process camera, or made with pantograph, divider and other such device.
Such lenses, called process lenses, produce the best image at a lens-to-subject distance of about 10 feet or less. 8-8 Another very important aspect of a process lens is its evenness of illumination across the focal plane.
Chromatic Aberration: In photographic or lithographic process lens, the result of the unwanted dispersion of light so that colors of the white light spectrum are focused on slightly different distances on a single plane.
Apochromat (APO) lenses have added correction for chromatic aberration.
Process lenses have extreme correction for aberrations of geometry (pincushion distortion, barrel distortion) and are generally intended for use at a specific distance.
 See also: Lens, Light, Photograph, Color, Image
|
