recently i saw an old kodak manual on this problem. There is no curve to apply to reciprocity. It is a linear logarithmic function. perfect exposure changes with time at a certain distance logrithmicaly with unchanging aperture. www.glassplatenegativehow-to.com
------ Original Message ----- From: Jeff Dilcher Sent: Tue, Jun 19, 2001 9:03am To: <pinhole-discussion@p at ???????> Subject: [pinhole-discussion] Reciprocity Problem *** Warning *** *** Technical Question Follows ** ** press delete key if technical questions bother you ** I have a technical question, that, perhaps someone on the list can help me with. Please respond directly if you like. I am trying to develop a mathematical function which will help determine reciprocity compensations. Initially, I would like to be able to submit a small set of reference values (metered exposure times along with exposure time compensation for reciprocity). Using these, I would like be able to enter in any exposure value, and get a corresponding compensated value on the reciprocity "curve". I am trying to boil this down into an algebraic equation as easily as is possible. I have quickly reached the endpoint of my math abilities. Can anyone provide a clue for me? _______________________________________________ Pinhole-Discussion mailing list Pinhole-Discussion@p at ??????? unsubscribe or change your account at http://www.???????/discussion/