Here's some first impressions and a few quick measurements:
I'm pleasantly surprised with the Optoma UHD65 so far. The one aspect I'd say that I wanted to see most on this unit was how well XPR (e-shift) performs. Now, while there are some slight oddities with single pixel test patterns (I took a quick look at the R.Masciola UHD test patterns), in practice it looks exceedingly similar to that of a good single chip .65" DLP projector in terms of pixel sharpness. Text looks how it should and about as good as I've seen it look with Sony's native 4K projectors. I guess what I'm trying to say is that if you didn't know this was an eshift unit, you'd actually think this projector had a native 4K image (until you looked close with some test patterns). That was a surprise. I was expecting text to look a bit more wonky, like how JVC's eshift units look, but it doesn't. I use an HTPC most of the time to feed video to my projectors and from my seated position text sure as hell looks like it's coming from a native 4K projector. The lens used in this projector is "good" for it's price, but it can't delineate pixels anywhere near as well as the better .95" DLP 1080p projectors, but again, it's hard to see that slight sharpness deficit from the seat, plus you gain literally 4 times the amount of pixels on screen, so there's absolutely no doubt in my mind that this projector will look considerably sharper than the best high end single (and 3-chip) 1080p DLP projectors out there if you were to compare a good quality 4K source on this projector versus the 1080p version of that same film on those 1080p projectors.
Here comes the contrast numbers. It will come to no surprise to many of you to hear that it isn't as good as most of the .95" DC3 and DC4 1080p projectors that came out about a decade ago. This is a shame but a lot of this comes down to physics. The size of the mirrors on these DLP DMDs make a big difference to contrast potential. The mirrors on those DC3/DC4 1080p DMP DMDs were simply a lot larger so they had the potential for more contrast than the mirrors found on this .67" DMD. At max zoom on the lens (so worst case scenario for on/off contrast) and in high lamp mode, I'm measuring 1456:1 native contrast and with the lamp dimming based "Dynamic Black" engaged we do see a considerable jump in contrast to a decent 5394:1 dynamic contrast. That's a nice ~3.5x increase in contrast performance. I should also note that Dynamic Black engaged hasn't really given me too many issues in it's "visibility". You can definitely leave this engaged without it being bothersome. That's a nice plus I also wasn't expecting. But I also haven't spent enough time with this unit to say how well it enhances contrast with actual content. What I mean is, I haven't spent enough time to see if there's a decent increase in contrast when real content is being displayed and if most of this ~3.5x increase is only for when a 100% all black image is on screen. Contrast performance is subjectively a lot better than I thought it was going to be from what I've seen so far and I think that is a good indication that contrast is being enhanced a decent amount with real content on screen.
Brightness performance from what I've measured out of the box is extremely close to Projector Central's review. See here
for those numbers. Reference Mode has the most accurate color out of the box and unfortunately this mode doesn't put out a "competitive' amount of lumens when we look at some of the other HDR compatible projectors like the similarly priced Epson 5040 and current JVCs and Sony 4K models. I'm measuring 850 lumens in high lamp mode and I'm sure this is going to go down a bit to further to pull in the white balance and color closer to D6500 and REC709. For most people this will be fine when it comes to SDR content, but unless you have a particularly small screen, HDR might not look at it's best on this unit. With that said, I haven't looked at any HDR content yet so maybe I'm wrong here.
Some other odds and ends. I measured input input lag with the Leo Bodnar lag tester at 75ms. But this isn't a 1080p native projector and the Leo Bodnar device only outputs 1080p so if you're feeding the projector a UHD or 4K image it will more than likely have a different amount of lag. Anything 1080p sent to this projector, however, will have about 75ms of input lag. I'd also like to comment and say that RBE (rainbows) are hardly an issue. Considering the brightness, I'm surprised I haven't seen more of them. This is also the quietest DLP projector I've had here. It's as quite as a current JVC projector in low lamp mode and has the potential to put out about as much light as a JVC in it's low lamp mode. Kudos to Optoma for this achievement. I was beginning to think all DLP projectors were doomed to be loud.
These are just some quick thoughts and measurements. I hope you find it helpful. I'll be spending some more time later with this projector to see how HDR looks. I'm honestly surprised a bit at how good overall this projector performs. It definitely took me for surprise.