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QTR-Quadtone RIP

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Re: [QuadtoneRIP] fine tuning .acv curves

2016-08-15 by Roy Harrington

Not sure if this is what you really want.
But the PS .acv's are limited to 14 points and only 8-bit accuracy.
If you use the QTR driver curves (explicit x,y coordinates) you can have
many more points and 16-bit accuracy. No visual curve display though.

Roy

On Mon, Aug 15, 2016 at 4:21 AM, stefanchristiansen@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:


I still haven't found a better tool than PS to edit the .acv curves I use in QTR.

I hate those tiny curve windows and inaccurate graphs.


My profiles (for negatives) use only four channels and one shade of ink at a time, and one same curve driving those channels (I'm simplifying a bit). No partition, no crossover points.
I don't use a densitometer, don't linearize or anything like that. I look at my carbon print, I modify the PS curve and reprint...

I'm rather happy with it but would like to have a better control on either fine tuning the curves or my profiles.
No way I will edit 256x4 numbers in a .quad files, but I'm OK with manually editing 21 values.
For the moment I put anchoring points on the PS curves and move those I want to modify.
With the eyedropper tool (16-bit) I check the values on the stepwedge that is opened in PS. 5% is now 642, etc…

Please, would anyone think of a better way to fine tune .acv curves (on mac)?
You understand I'm not familiar with linearization, but could the Drop-Quad-Profile script help me?
What kind of .txt file should I use? Would it be possible to convert PS's eyedropper readings into appropriate values? For exemple, I would like my 5% patch to have a 720 value instead of 642. Is this something I could use somehow with the droplet?

Thank you very much for your attention and help.

Best regards,


Stefan Christiansen







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