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QTR-Quadtone RIP

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Re: [QuadtoneRIP] Help with a "bit of simple math".

2015-10-17 by paulmwhiting@...

A while back I uploaded a pdf to the Files/Tools library, which explains how to use a 20 step grey scale, flat bed scanner and a spreadsheet to create that forumula. The problem I had with the interpolation method is that it is a linear approach whereas the pdf (called QTR Curve Making) file lets you plot the curve and then generate a curve and logarithmic formula in a spreadsheet. You don't have to know what a logarithm is.

I won't try and explain it further here, but simply suggest taking a look at the pdf. It may look confusing at first read (it certainly was confusing for me!) but after a while it began to sink in.

In fact it's time for me to dust off this method when I break open a bottle of the new Eboni black, I understand it is slightly warmer than the previous version. This will require a new curve for the papers I use.

Hope this helps,

Paul

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