In a way, I do have a known issue I am dealing with. That is, in the fine art scanning work I do, I often have to capture subtle highlight details.
I figure that there is at least one if not a couple of factors that will affect the degree to which I can satisfactorily capture highlight details:
The first is the luminosity of the white patch in the scanner target used.
And, possibly, the highest white point to which the scanner is calibrated.
My initial question was partly based on my reasoning that a better scanner profile would be obtained if the scanner white and the target white are identical.
In my case, Lab = 98.0 -0.2 -2.0.
The Epson cal strip L = 96 (I’ve forgotten what the ab values are.)
Frankly, I haven’t really taken the time to definitively determine whether substituting the cal strip has improved my ability to capture highlight detail beyond merely using a suitable scanner target (in my case, the ColorChecker DC with modified center white patch).
On casual observation though, I think I’m experiencing slightly better results using my own cal strip.