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QTR-Quadtone RIP

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I don't understand gamma, I guess.

2015-08-02 by jp432r@...

I think the problem I'm having has to do with gamma, but I don't have a solid grasp of what gamma does in each part of the environment I can't work out a solution. In fact I'm not really sure if it's the problem.

I'm making digital negatives for contact printing

I have carefully calibrated QTR using a gamma of 1.8. Step tablets print great. Scans with an embedded gamma of 1.8 print well, but the stuff I shot with my digital camera, post processed in Photoshop, inverted to negative, and printed using the calibrated QTR settings print very poorly. Very dark and muddy.

I don't really know the gamma of the files my camera creates, but I assume it is 2.1 or 2.2.
I've searched the web for info on converting a file's embedded profile from 2.x to 1.8 without luck.

I could start over and create a step tablet with gamma 2.1 and then recalibrate, but I've been working on this a week and I'm hoping to avoid that.

Does anyone have any suggestions on how to approach the problem?

Jeff


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