Just get the cross in the target circle throughout the grey scale
Then use a Quick Profile to check the underlying gamut
sure, I could do that by using the remote control to align all crosses into the middle of the circle.
But CM do this automatically for me via RS232 DirectDataControl Calman <-> JVC, up to 21 pts in grayscale. By hand (using the remote control) I could adjust much less than 21 points in the JVC's OSD user gamma equalizer.
Calman's autocal "Guesswork" could be better in lower stimulus levels, but the development seems not to be really interested in improvement suggestions like a smaller adjustment stepping size to get the results closer to the targets
And no, the guess-work approach is not better in the shadows - that is simple a function of the probe accuracy, and display limitations (back-light bleed).
Oh, I think you got me wrong. I meant, Calman's autocal functionality via DDC is not as accurate as it could be regarding how "fine" one grayscale point (IRE level) could be adjusted JVC internally. CM use a 0,3 stepping between 2 values for approaching the target, but the JVC supports 0,1 as lowest step size. Therewith a grayscale autocal result would be much more accurate. I do this always by hand after the Calman grayscale autocal, because especially the lower levels (5 ... 15 IRE) are not really "dark gray", they sometimes are slightly green or red or blue. And it's not an issue of my probe - the accuracy of the i1D3 (profiled with the i1D2) is very good at all levels!
We may add Delta-E reports in a future release, but would like them to be better than the standard offerings, so are researching ideas at the moment...
If this could be true some day, I think, many of your customers would appreciate it! That's a point I miss in LS, because if people talk together about their display calibrations, they commonly talking about deltaE results (or just only to compare calibrations from time to time using data with "numbers"). So it's always a bit hard to say "my LightSpace 3D Cube view looks great, but sorry, can't say anything about grayscale deltaE ... " ... or so. But as said - not really important; the visual result makes it all.
Any display fluctuations are just not an issue as the calibration process (the LUT generation) uses all the profile data to calibrate each individual point, so also managed any fluctuations.
Hmmm ... but what, if the luminance will fluctuate during measuring all the patches - or is saturation + hue of a patch all, LightSpace needs for LUT calculation? But remember, these bad fluctuations are sporadically (caused by slightly varying heat inside the lamp, I guess) and not always on the same "patch". So a calculated LUT will match to the situation as the measurement was done, but at runtime the LUT may not match anymore because of new fluctuations. I think, that's a problem, no calibration system can solve. So I hope, in a few years we will have affordable home cinema projectors with bright LEDs / much more stable light sources than in actual PJ's with UHP bulbs.