Surface characterization and monitoring of surface changes after conservation treatments of silver gelatin photographic papers using confocal microscopy

Surface metrology techniques that are non-perturbing (non-contact, non-invasive, and non-destructive) are well suited to in situ surface studies of historical and fine art photographs. They allow for the quantitative examination of the microstructure of the photograph surface, thereby, offering an important advancement in the examination, documentation, and characterization of silver gelatin photographs and other modern and/or historic imaging materials. This article presents the application of an optical confocal scanning disk microscopy system to the qualitative and quantitative characterization and assessment of a silver gelatin photographic paper, Ilford Glossy, submitted to different humidification and flattening protocols.