After much work and trepidation, I am at the point where I can release the findings enclosed in this PDF: https://1drv.ms/b/s!AkD78CVR1NBqkt8B_bNYu4eo-D74bQ?e=K6gqTQ My goal was to come up with some kind of useful visualization for a monitor Luminance and chromaticity variation, across its surface. I experimented with different approaches and I'd be interested in any feedback. I wish I had initially measured the three monitors enclosed in this study so that I would have some kind of point of comparison - my bad. All I can say is that I enjoyed these monitors for many years and even though they're "off a little", now, they still serve useful purposes. These days, I'm in the market for a new LED 32 incher (the new Apple Pro is outside of my range.). I've emailed a few monitor manufacturers with regards to the kind of warranty they can give in terms of "uniformity" (but not Apple? John, if you have information you can share, here.). So far, no answer. For a Display to have no more than 10% deviation in Luminance or less than 5 dE2000, from the center of the screen, as ISO 14861:2015 and ISO-13646 call for, given the "natural" drifting to be expected with aging of ANY monitors, means pretty stringent requirements, initially. / Roger Breton (from a cold -22C, here, in Montreal.)