Hi Phil,
It's hard to state with any certainty because we don't have the whole story yet, for example, is this after you applied curves to a linear run?
But I can state that I often see changes in behavior to the wCh between the 60-75% inking range. And often this is due to ink trapping for your particular inkset. Once the paper starts filling up with dots of CMY, and the paper begins to take on a lot of water after going through multiple cylinders, the inks don't always lay down as well as they should. For example, if you're running KCMY, the yellow may be having difficulty laying down on top of the cyan and magenta. So visually, at this range, this could possibly cause the color to look too blue and too magenta.
I can only guess at this point, but I would definitely suspect that may be happening to you. Hope you get more answers that will help you solve your dilemma!
Nikki
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Nicole Orr G7+ Expert
Owner, President
Futurepointe
Colchester CT
(860) 861-7929
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Original Message:
Sent: 09-12-2025 03:57 PM
From: Phil Courterelle
Subject: Weighted Graybalance - a* b* crisscross
Hi all
Looking for insight into an odd graybalance result. Scan failed with graybalance average and max out of tolerance. The weighted chart (bottom right) shows CMY graybalance to be shifted to the warm side. All reasonable. But the a + b lines crisscross at 60% dramatically. I've not seen that behaviour before. Any thoughts? Significance?
SBS paperboard, Gracol 2006.
Cheers
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Phil Courterelle
Print Operations Manager
Great Little Box Company
Richmond BC
(604) 301-3700
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