Printer point

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.^[1]

This numbering scheme is used in photographic printing and photographic filters.

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.^[2]

References

1. "Spectra Film Gate Photometer II". Spectracine.com. Retrieved April 5, 2012.
2. Richard Kirk (2010), Standard Colour Spaces, FilmLight Ltd.