an instrument for testing the sensitivity of various types of film, consisting of an apparatus for exposing successive parts of the film to a light of standard intensity at successively increasing lengths of exposure.
Origin of sensitometer
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
an instrument for measuring the sensitivity to light of a photographic material over a range of exposures
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012