How to make the best emulsion, or why "Silver Rich" is a myth.

[wirehead]

How does sub-surface scattering play in to this? Iwould imagine (I spent a bunch of time in college doing ray-tracing and computer graphics) that sometimes light can be reflected around the surface layer, especially from oblique angles.

 

[Photo Engineer]

Sub-surface scattering reduces sharpness during exposure, and is dependant on layer thickness and amount and size of the silver grains. After processing, sub-surface scattering attenuates light and limits dmax, as explained above, to a value of about 1.8 for matte papers and about 2.2 for glossy papers.

Oblique or incident light will vary as a function of the surface of the paper, and can cause very unusual effects. I would not care to discuss it here. It takes a very sophisticated piece of equipment to measure the effects. That is called goniophotometry.

PE