Monday, January 15, 2007
Since Kurt is using Foma 200, and I like this film, too, and have some on hand, I finally made time to test it in the new version of Hypercat. Despite Kurt's report of thin negs at 5:30, my test results show 5:00 is about right for printing on a middle grade of paper with an Exposure Scale of 1.15, or about Grade 1 1/2-2. I haven't verified these results in the field, so consider this a starting point for personal testing. For those unfamiliar with BTZS data, SBR refers to Subject Brightness Range, and 7 correlates to a normal scene. Average Gradient is a measure of contrast, like CI, and EFS is Effective Film Speed. ES stands for Exposure Scale and represents the contrast/grade of the paper. Grade 2 papers typically have an ES ranging from .95-1.15, so 1.15 is on the border between grades 1 and 2. This data is consistent with printing using a diffuse light source, as in a cold light or dichroic color head, or contact printing. The use of a condenser enlarger would require a lower contrast negative to print on the same ES/grade of paper.
This data suggests ther isn't much room for contraction development by reducing development time, and reducing agitation might result in streaking, so a more dilute working solution would probably be most practical, or perhaps reduced carbonate concentration. I'll try both, eventually.
Film: Foma 200