Printing with a not-quite-linear curve

As usual, I’m having a difficult time linearizing a quad for New Cyanotype (I do a complete re-linearization every time I make a new batch of sensitizer). After a couple of iterations, my curve is close to linear, but the negative appears to need a bit more density throughout. Here’s the smoother curve:


To my eye, the 129-step target looked beautiful. I was surprised to see that it was still too dark.

Here is my question: if I use this curve together with an icc profile (QTR-Create-ICC), can I deal with the lack of linearity by adjustments to the tone curve during soft proofing?

If I do another iteration of linearization, I run the risk of QTR-Linearize-Quad adding too much density, flipping the smoother curve to the other side of the line. This is a problem with New Cyanotype. It is very sensitive to slight variations in darkroom variables.

This is fine. Better than the vast majority of all cyanotypes. Cyanotypes (or any darkroom printing) is inherently unstable. There will be variations based on small changes in oxidation or paper humidity, etc. Don’t worry. Print and be happy my friend.


Good to know, thanks. I’ve gotten a lot closer to a straight line in all my past linearizations, but it usually takes three or four iterations to get there. I always wondered how much marginal benefit there was in doing this. Anyway, I’m tired of linearizing, so I’ll go with this one.

Nevertheless, he persisted.

That’s three iterations starting with master: master-lin, master-lin-lin, and master-lin-lin-lin. Each iteration got progressively close to linear:

In your linearization of cyanotype, how many iterations do you recall doing?

1 Like