re: ink restrictions
re: ink restrictions
- Subject: re: ink restrictions
- From: David Wollmann <email@hidden>
- Date: Mon, 18 Dec 2000 19:27:03 -0700
- Organization: Luna Vista Imaging
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I set the m3 and c3
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threshold as high as possible so that the 200% red green and blue on the
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darkinkrestrictions.tif are just becoming dry in the normal print process.
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this due to have the maxium possible hues.
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Do you mean the >100%< Red, Green, and Blue patches? So, rather then
using the >L< patches of the darkinkrestriction.tif, you simply observe
how the Red, Green, and Blue 100% patches dry, and then adjust the
threshold for m3, c3, and Y as needed? If these patches are too wet and
taking to long to dry, do you reduce all 3 equally? I ask because yellow
always seems to produce a lower Dmax, with flatter density curve versus
the other inks. I've also noticed that if the yellow is set too high it
will sit on top the blacks causing them to appear greenish.
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you could use a desitometer to measure the max dens but I would't do
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this cause to what will you refer to? some times I use the max denses of
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euroscale (fogra) but just as an Idea where I am...
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Being on this side of the pond ;-), I was wondering if using SWOP max
densities might help give an idea of where I'm at, and perhaps help
determine if I've gone below these >standard< Dmax settings.
The Onyx manual seems to raise more questions then it answers when
trying to set Ink Restrictions. This step does seem important since this
establishes the foundation for everything that happens later.
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[wollmann] > The manuel is not clear here about light and medium inks, but with the
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> medium shade set to 10% less then the dark shade, what about the light
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> shade? Should it be set to 10% below the medium shade or both medium and
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> light set to 10% less then the Dark Ink restriction?
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[Peter Henry] yes this is the idea. what I do is I use a raster
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microscope and adjust the thresholds in that way that the dark pixels are
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starting in the brighter inks more late as early in order to avoid
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peppering.
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Well, I need to rush right out and get myself a Raster Microscope, my
chemistry set never came with one of those! ;-) Must be a cool tool,
but sounds expensive too. What about a strong loupe?
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[wollmann] Should it be set to 10% below the medium shade or both medium and
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> light set to 10% less then the Dark Ink restriction?
>
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[Peter Henry] ...this can be 10% less but sometimes I keep it at 100%.
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100%... Meaning that the light and medium inks would be set to 100% of
the value of the reduced dark ink, right? It sounds generally you do set
the lighter shades of ink to a value 10% below the dark inks, and with
the ColorSpan printers, sometimes it is okay to set the light values
higher then the others, logic aside.
When using the darkinkrestriction.tif how to you select your black
patch?
Thanks,
David Wollmann.