Hi All I was looking for photo colorization software and found a place that does restoration, colorization, etc. Anyway they had a nice piece on the history of the different photo processes that would be of interest. It is not too elaborate and was about as much as this photo dummy needed to know. Try: Guide to Identifying your Family Photos http://www.light-magic.com/identify.html Larry Friend (Black Buffalo) niidji@mchsi.com