So I did this little test this morning. First off, people should be aware that this is basically a "worst case" scenario--pure white against pure black, and a very tiny small area of white. That's basically a guaranteed way to make any FALD display show some interesting effects. I think the camera may be exaggerating the effect a little, as I did the same test on my nano XDR and it was not nearly as strong. Had I not been looking for it I might not have noticed. I did try it in several different modes, such as the standard 500 nits Apple Display mode and in the 1600 nits ProDisplay XDR mode and it was pretty much the same no matter what.
I also looked for blooming, with the lights turned off and the room completely black. You should note that this is NOT how standard color grading is done, BTW--most guides for color grading recommend having a D65 light at a fixed lumen value behind you, to replicate "normal" viewing and light conditions. That said, it is a great way to stress test the blooming. With the same tiny patch of white on a pure black background I can just barely see some purplish-blue blooming when I lean pretty far off-axis from straight on viewing.
On the other hand in the same conditions a 27" iMac and my LG 5K don't even look black--the XDR just blows them away for producing a true black. Check out the attached photo to compare. Can you replace a $35-45K reference monitor with an XDR? No. Is it way closer to a true a reference monitor than a regular desktop display, definitely. How close? I have no idea, but I can tell you that it's way better in daily use than my LG 5K, and the price for a 32" 6K display with the color gamut, FALD and brightness capabilities are pretty much unmatched right now. The AsusProArt PA32UCX is close, but only 4K, and not as bright (1400 nits). It will set you back $3999, but the stand is included. It does have more FALD zones though, which should help with blooming in theory, but it's hard to say given the other technology Apple has used. Asus is releasing another version of this display soon with 1600 nits, but it will also only be 4K (although with a 120 Hz refresh rate and double the zones). The price isn't known yet, but it's presumed it will run more than the lower-spec version. In that light the Apple display doesn't seem so expensive, well except for that crazy stand price.
Now for that photo showing how black black really is on the XDR. From left to right, it's my 27" iMac, the 5K LG Ultrafine and then the nano XDR. All with a jet black screen (
www.lightbleedtest.com).
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