Printer point
Encyclopedia
In photography
, a printer point is a unit of relative exposure, in printing a negative, equal to a 1/12 of a stop
or 0.025 Log(base 10) unit (one-fortieth of a decade) of exposure ratio http://www.spectracine.com/product_filmgate.html.
This numbering scheme is used in photographic printing
and photographic filter
s.
Increasing or decreasing the light by twelve points increases or decreases the exposure by a factor of two. Such adjustments are used for darkness and color adjustment in photographic enlargers, for example. A one-stop change in the exposure of a negative may require only an adjustment of about 6 to 8 printer points in printing, depending on the gamma of the film.
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
, a printer point is a unit of relative exposure, in printing a negative, equal to a 1/12 of a stop
F-number
In optics, the f-number of an optical system expresses the diameter of the entrance pupil in terms of the focal length of the lens; in simpler terms, the f-number is the focal length divided by the "effective" aperture diameter...
or 0.025 Log(base 10) unit (one-fortieth of a decade) of exposure ratio http://www.spectracine.com/product_filmgate.html.
This numbering scheme is used in photographic printing
Photographic printing
Photographic printing is the process of producing a final image on paper for viewing, using chemically sensitized paper. The paper is exposed to a photographic negative, a positive transparency , or a digital image file projected using an enlarger or digital exposure unit such as a LightJet printer...
and photographic filter
Photographic filter
In photography and videography, a filter is a camera accessory consisting of an optical filter that can be inserted in the optical path. The filter can be a square or oblong shape mounted in a holder accessory, or, more commonly, a glass or plastic disk with a metal or plastic ring frame, which...
s.
Increasing or decreasing the light by twelve points increases or decreases the exposure by a factor of two. Such adjustments are used for darkness and color adjustment in photographic enlargers, for example. A one-stop change in the exposure of a negative may require only an adjustment of about 6 to 8 printer points in printing, depending on the gamma of the film.