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Re: Trouble with Custom QTR Curves

2016-04-20 by brian_downunda@...

@Roy - Back in post #23, artodd138 asked "does anyone have a graph of L* values that would appear linear to a standard observer". This question does not mention monitor-to-print matching, but all my attempts to guess an answer to this question have been dragged off into the weeds of matching. I'm going to make one last attempt at this.

Let's suppose we are in a room with no monitor, so no concept of matching. We place a piece of paper in front of a viewer with a series of unlabelled, evenly-spaced grey patches, i.e. evenly spaced luminosity values, ranging from white to black, and ask them if they are evenly spaced. It's my understanding that they would say no. So the question is, what series of patches would they consider evenly spaced? Again my understanding is that if the evenly spaced luminosity patches are converted to an ICC from QTR-Create-ICC and reprinted, then the observer would probably say yes.

I seem to recall a post somewhere in the past where you (Roy) said this, but can't locate it. Is this an accurate memory, or a manufactured, false one? If it's accurate, then there's the answer to artodd138's abstract, conceptual question. If my recollection is false, then I'll pull my head in and go away, in which case artodd138 will have to find the answer elsewhere.

---In QuadtoneRIP@yahoogroups.com, <roy@...> wrote :

There's a lot of pretty loose talk about linearity.

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