Duane Hall wrote:
Attached is a Hutchcolor.cht that works with the above example.
Thanks. This gives me a better profile than two other programs I tried, both of which were unusable due to severe posterization.
Note that it's also part of V0.70Beta6, as is a template for the ColorCheckerSG (although it would be good if someone with this chart could test it out !)
If this .cht were to be used with a Hutchcolor target from a different batch, am I right that one would need to change the list of expected XYZ values?
No it should work fine as is. The expected XYZ values are just used for chart orientation. The chart recognition handles any chart orientation, and since the arrangement of squares is symmetric, a way of identifying the orientation is by the (approximate) expected patch values. The important file is the CIE reference file, which you would normally download from the Hutchcolor website.
I applied the argyll profile to a Granger Rainbow, and it seems normal except for some oddness in the blues. Is this something to be worried about? I haven't noticed the effect in any real-world images.
Hard to say without having the details. Graeme Gill.