New Calibration Tool, Excel Download - Page 5

Originally Posted by TomHuffman

The problem with this is that different dE formulas yield different--often substantially different--results in this regard. Greg uses CIELUV exclusively, which I have much less faith in.

Indeed, this shows just what I have been talking about for some time. Take this oversaturated, but otherwise accurate, green: x0.296, y0.676, Y0.7152 and run the solver for both CIELUV and CIE94 (assume Rec. 709). You get radically different recommendations.
CIE94: 0.687 (Actually, a range of values between 0.674-0.701 all yield the same result. 0.687 is a median value)
CIELUV: 0.532 (a range of 0.518-0.546)

For a variety of reasons, I think that CIE94 gets the correct result.

BTW, I don't see how you are getting you %C and %H error values. The oversaturated green I defined above has perfect hue, yet your spreadsheet gives it a percentage error of %39.3.

Originally Posted by stereomandan

I included some HCFR specific % bar values for 100% and 75% saturation points in the calibration aid tab.

I explain it in the "Special Hint" section of Post #1 in my Epson calibration thread.

http://www.avsforum.com/avs-vb/showt...7#post16166537

Dan