Photographic relief image studies using laser scanning confocal microscopy

A study of relief image characteristics in photographic emulsions is made using laser scanning confocal microscopy. Confocal microscopy is used in a novel application to measure the emulsion surface and provide digital, topographical images. The relationship between height of relief image and developed density is analysed for 50 mu m wide line images formed on 35mm film, developed using fine grain and tanning developers. The measurements made with this technique are compared with earlier work that used fringe pattern analysis and the new results show good agreement with earlier findings. The higher accuracy of confocal microscopy is used to present new findings regarding the presence of adjacency effects in the relief image. The use of confocal 3-dimensional imaging in emulsion artefact characterization is demonstrated.