U of S | Mailing List Archive | alt-photo-process-l | Re: Two tricolor prints

Re: Two tricolor prints

I am trying to digest all that :--).  Comments below:

On Sep 26, 2007, at 11:38 AM, Marek Matusz wrote:

Drastic curves, especially S shape can alter colors quite unpredictably.
No doubt this is true, but not sure what it has to do with my examples, since there's no such curve involved, and I haven't altered the colors of the original file in making the separations.

The other simpler reason might be that you simply have enough density to block it in one negative used to print blue, but by applying curve you have taken the density in the negative away and now you are able to print the unwanted blue. This is something that I watch for making separations. Are there places in the print that require clean two color mixes and is the color separation negative of the third primary sufficently dense to block the third color layer.
Surely that would be a smart thing to do, if one could tell by looking. But since the only difference between the two negatives where I don't want tone (on the poppies) is the negative color (the density of the file is the same at that point) I can't see any difference beween them. I do know that "screen"mode, which I was taught to use for color layers, lightens the image underneath, so I thought a-ha, that's it! Using "screen" mode lightens the negative, so it's not dense enough in the lightest parts and prints some tone. But then I realized that doesn't explain why with other negatives, the same color in the same kind of "screen" overlay prints whites fine.