GB572518A - Improvements in photographic sensitometry - Google Patents

Abstract

572,518. Sensitometry. KODAK, Ltd. (Eastman Kodak Co., Jones, L. A., Nelson,. C. N., and Clark, L. D.). Aug. 6, 1943, No. 12718. [Class 98 (i)] A sensitometer tablet for making a sensitometric strip (e.g. on a printing paper the sensitiveness of which is to be ascertained), comprises in its simplest form a strip, Fig. 1, ranging from high densities to low densities in which there is a constant increment between each area in the low density range and a constant increment in the high density range. The low density increment may be between .01 and .06 (e.g. .02) and the high increment between .03 and .12 (e.g. .06). In Fig. 3, each area comprises a pair of adjacent areas with a small increment between the members of each pair (e.g. .02 for the low density pairs and .06 for the high density pairs) with a constant difference (e.g. .1) between steps throughout. In Fig. 4, the steps are arranged around a circle with the higher density of each pair comprising a circular area C on a background B of the lower density. The area D and the outside area are formed of a uniform density approximating to step 8 simulating the average density of most negatives when prints are made. In lieu of circles C each area may be of a different shape.