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oxident
07-12-2017, 10:46 PM
Sorry, didn't know a better way to summarize this question ;-)

I have created a custom profile and calibration set using CPS and it works fine on my regular paper (bright white Hammermill-like). But whenever I print on a different type of paper my customers bring with them (mostly slight yellow Munken paper), grey areas turn to green/yellow.

I do understand that the white point of the media could cause this behaviour and everything's fine again if I create a new profile for that specific paper but I'm wondering why it even looks okay if I'm using the Fiery's stock profile (C71hc uncoated paper) instead of my own profile.

Could this indicate that I have done something wrong when creating my custom profile?

Or is the printer's internal linearization (which I turn off for customers' own media) the cause for those color shifts?

StarDigital
07-13-2017, 06:37 AM
have you tried different variations? You said you turned off the linearization, have you tried it with it on? Does the yellowish show in image viewer. Is the gray an RGB or CMYK, for RGB you can set to remain as a gray. have you tried with/without APPE? Tried difference source calibrations? There are allot of things that can possibly cause this, knowing what doesn't would help. Also make sure all patches are installed, i believe i saw a patch similar to this on one of my machines awhile ago.

oxident
07-13-2017, 07:38 AM
Sorry for not being so specific. I didn't want to start with so much content to read :rolleyes:


have you tried different variations?
Absolutely. That how I found out that the stock profile does such a pretty good work ;-)

You said you turned off the linearization, have you tried it with it on?
No, because this regular "wastes" about ten sheets every 400 prints and the customer didn't supply enough spare sheets for that.

Does the yellowish show in image viewer.
No, not at all. The distorted portions of the affected images are around 3-5% CMY (slightly uneven).

Is the gray an RGB or CMYK, for RGB you can set to remain as a gray.The images are CMYK with embedded profiles. No way to force it using gray only (I've tried it ... it remains CMY).

have you tried with/without APPE?
CPSI looks a little bit different but not really better. But I had to use APPE because there are some cross hatches which get "broken" (uneven line widths) when using CPSI.[/QUOTE]

Tried difference source calibrations?
Yes, but as soon as I choose a different source profile (and disabling the use of embedded profiles), the images came out very dark, compared to what I see in Acrobat's output preview (which the customer verified to be the correct appearance).

There are allot of things that can possibly cause this, knowing what doesn't would help. Also make sure all patches are installed, i believe i saw a patch similar to this on one of my machines awhile ago.
The IC-308 is already at its most recent patch level.

Maybe it's really a problem with using profiles created when the machine's internal density management is enabled on media where it's disabled. But I didn't expect such a huge problem.

Lou_P
07-13-2017, 08:44 AM
What you are seeing is what we would expect. You need to make a custom profile for each paper, and using one made for one paper on another paper is not expected to yield the best resutls - or you woudn't need to make a profile for each paper in the first place.

So it sounds like your profiling procedure is working fine.

The best guess at why the factory profile works on the yellowish paper is that it was probably made for a yellowish paper.

If you want to send me a private note with all the profiles attached we can have a look at this.

~Lou

oxident
07-14-2017, 04:19 PM
Thanks for all of your valueable information. I guess there's no need to investigate further.

After inspecting the output profile a little bit deeper, I've seen that my custom profile is indeed adding a small amount of yellow ink to light (RGB-)gray colors in order to get a neutral balance on my white paper. This results in too much yellow on yellow paper ;-)

The stock profile doesn't do that (it's using 1% CMY) and therefore, the effect doesn't show up there.