U of S | Mailing List Archive | alt-photo-process-l | Re: question about gum curves

Re: question about gum curves

Hi Charles,
Interesting that you should ask this question: I have calculated the curve for a blue red/magenta and a really bright orange red, and the curves are different. However, when I curve my individual negatives I always use the magenta one because more often than not, I am leaning toward a blue red and not a brick red, and then if I have to use a different red with the same negative, I expose longer. What I would find is that the brick red would take longer to expose and flakes more. But the comparison I did, to see if the reds required drastically different curves, was with a really bright orangey red that I would rarely use in practice anyway.
----- Original Message ----- From: "ryberg" <cryberg@comcast.net>
To: <alt-photo-process-l@usask.ca>
Sent: Tuesday, October 24, 2006 12:36 PM
Subject: question about gum curves

Do you folks who curve each gum color individually find that a curve for one red is pretty much the same as for another red? Or do you need to make individual curves for each pigment? And, what about paper--do you need different curves for one pigment depending on which paper you use?
Thanks in advance.
Charles Portland OR