Jr. Jarvis, ON DYE CLOUD DIFFUSION AND THE IMAGE QUALITY OF COLOR NEGATIVE PHOTOGRAPHIC MATERIALS, Journal of Photographic Science, 43(4), 1995, pp. 136-143
The impact of dye cloud diffusion on the signal recording and noise pr
operties of a colour negative photographic material has been studied.
A mathematical model has been established which quantitatively links m
odulation transfer function (MTF), noise power spectrum and granularit
y to the size and morphological features of dye clouds for a large var
iation in cloud diffusion. The basic features of the model have been e
xperimentally examined using three techniques for varying the extent o
f dye diffusion; 1) A variation in image coupler laydown, 2) Adding a
black-and-white developing agent to the colour developer solution and,
3) immersing a fully exposed and processed film strip in an alkaline
alcohol-water solution. In all cases, the model was seen to describe i
mage structure performance realistically. Also the link between colour
negative dye cloud diffusion and predicted final print sharpness and
graininess has been quantified.