A forum for users and potential users of Hypercat, a high acutance catechol-based, tanning/staining developer.
Monday, January 15, 2007
Foma 200
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
Format: 120
EI: 200
Dilution: 1:10:300
Volume: 500ml
time: 5:00
Temp: 70F
Agitation: 0:10/1:00
Hello Jay,
ReplyDeleteThank you for the test results. That helps to narrow things down to my camera or the light meter. I will try again with another. I am also going to print some of the negatives on Thursday, I might be surprised to find the negatives are not as thin as I thought.
Thank you for all the work you do.
Kurt
Hello jay,
ReplyDeleteJust a question about the HYPERCAT formula -is the sodium carbonate anhydrous?
Would 200g of household sodium carbonate be just as good?
Love your photographs by the way-they are a very beautiful and tender.
Peter
Hi Peter.
ReplyDeleteThank you for your kind comments. Household sodium carbonate is perfectly adequate. I often use pH Plus, intended for swimming pools, purchased at Walmart. Good luck, and thanks again.
Jay
Thanks for all the great info,
ReplyDeleteI will be making some 16x20 negs
(portraits) from aphs with hypercat
Rated at about iso 4
Any advice/suggestions
Thanks