The only situation i am going in touch with DeltaE2000 in my daily work is the GMG-Label which verifies a digital hardproof (printed on an EPSON SC P5000) or not:
For more accuracy i would assume that "the same yellow" (c:h) is only the same when it is printed not lighter or darker (L)? So i would say, all are equally important.
Especially the DE´00 is even more "tolerable"/"the value sounds nicer, because it is smaller" as itself compared with older ones (using DE CIE76, CIE94...):
Lab 86/-4/75 with 90/-3/78:
in this other example i try to proof that there is an importance if you will use the values for math as a base for "judging" (or using in a mathematical content ...), nevertheless that the ability of the human eye is limited to underline this fact... ;-)
But i am not able to explain the used formula in detail and so i can not really check Steve´s vote in an other way:
In which other situations you are looking at DE´00 in (daily) print bussiness?
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