BS ISO 18909:2022

Photography. Processed photographic colour films and paper prints. Methods for measuring image stability. Black leads. Bending strengths of HB leads | Status: Current

1 Scope This document describes test methods for determining the long-term dark storage stability of colour photographic images and the colour stability of such images when subjected to certain illuminants at specified temperatures and relative humidities. This document is applicable to colour photographic images made with traditional, continuous-tone photographic materials with images formed with dyes. These images are generated with chromogenic, silver dye-bleach, dye transfer, and dye-diffusion-transfer instant systems. The tests have not been verified for evaluating the stability of colour images produced with dry- and liquid-toner electrophotography, thermal dye transfer (sometimes called dye sublimation), ink jet, pigment-gelatin systems, offset lithography, gravure and related colour imaging systems. If these reflection print materials, including silver halide (chromogenic), are digitally printed, refer to ISO 18936, ISO 18941, ISO 18946, and ISO 18949 for dark stability tests, and the ISO 18937 series for light stability tests. This document does not include test procedures for the physical stability of images, supports or binder materials. However, it is recognized that in some instances, physical degradation such as support embrittlement, emulsion cracking or delamination of an image layer from its support, rather than image stability, will determine the useful life of a colour film or print material.