Projector Reviews

Optoma UHD51A 4K Home Theater Projector Review: Special Features 2

Optoma UHD51A  Projector Review – Special Features Page 2: 3D support, 4K Multimedia Player, Brilliant Color, Lamp Life, HDR10, Color Wheel and Rainbow Effect

UHD51A Supports 3D

Hooray! I always applaud having 3D support. There’s no standard for 4K 3D, so movies, etc., coming out in 3D are all 1080p. That’s fine. 3D makes great sense, improves immersion, on the large screen, whether in the movie theater or in your place. 3D doesn’t really cut while sitting 15 feet from some 65” TV. But 12 feet from a 110” screen – a whole different world. Optoma’s 3D is clean – free of crosstalk. Glasses are not included. (But at least they are relatively inexpensive these days – $20 a pair or less.)

This Optoma supports all the usual 3D formats including frame packing – Blu-ray 3D.

4K Multimedia Player


It only makes sense to support 4K for our phones and cameras stills and videos. That said, this is one of the few projectors with a media player than can handle both 4K videos and stills, even videos with HDR. I shot a lot of footage a couple weeks ago, in Alaska using my iPhone X. I managed to extract some of my 4K video stored up on iCloud, and wrestled it onto a USB thumb drive. It looked great projected in 4K.

The player can mostly be controlled with your voice, thanks to Alexa Skills commands, as mentioned. Play, Pause, Stop, Next, Previous, FastForward, and Rewind. Just drop in the USB drive in the USB port labeled USB Media Reader toward the right rear.

Brilliant Color

The UHD51A offers Brilliant Color – which is found on most home DLP projectors, but each manufacturer implements differently. On this Optoma, there is a significant difference between On and Off, with settings from 1 to 10, in terms of color, saturation, dynamics, whatever tools Texas Instruments packs into their Brilliant Color toolkit for developers. Eric found Brilliant Color on 10 worked well for his calibrations so that’s what I’m viewing.

Brilliant Color On
UHD51 - Brilliant Color set to the maximum: 10

Brilliant Color off
UHD51A: Brilliant Color on 1, which should be Off, there is no specific Off setting

Dynamic Black

This is another feature found on many home DLP projectors. The idea is similar to a dynamic iris. Dynamic Black dims lamp brightness and adjusts the dynamics to lower overall black levels. Manufacturers have had mixed success, because lamps just can’t dim and brighten back up fast enough. As a result, it tends to be noticeable, if the solution dims down a lot, or it only dims minimally to be un-noticeable. But in the second case it’s barely moving the bar on black levels compared to a good iris. (Or at least that’s my best attempt to describe.)

Dynamic Black on Passengers scene
This very dark scene near the end of Passengers, gets a small but nice improvement in black levels with Dynamic Black engaged!

Optoma seems to have found a decent compromise with the HD51A’s dimming. It’s not doing a whole lot, but then its slowness doesn’t become noticeable. It doesn’t get the black levels all that close to the Epson 5040UB, which is pretty much my benchmark for affordable serious black level performance.


HDR image from Ghostbusters
HDR makes a scene like this look more spectacular, richer colors, more dynamic range. The brighter the projector, the easier to properly tackle HDR content.

UHD51A HDR supports HDR10, which is the most widely used standard for High Dynamic range. There are also both a hardware solution from Dolby, and HLG, for streaming. HDR10 is the HDR standard for 4K UHD Blu-ray, but the UHD51A does not, at this time support HLG – Hybrid Log Gamma, geared primarily for streaming. Now most streaming that I’ve encountered (Netflix) that is 4K doesn’t support any High Dynamic Range yet (i.e. Blacklist in 4K).  This is the kind of additional capability that Optoma could conceivably add via firmware upgrade, but there’s also no sure reason to expect them to add that. HLG is mostly supported these days in newer, but also more expensive 4K capable projectors.

UHD51A Lamp Life

pano of room lighting
Pano of room lighting conditions, sunny day, shutters partially to 50% open - Super Bowl game

Impressive. Optoma’s spec’d the UHD51A at 4000 hours at full brightness. In Eco, that extends to a really impressive 10,000 hours – 5 years of 20 hours a week! There’s one more mode, which claims 15,000 but that more or less assumes that a lot of those hours will be when you left the projector on, and it was smart enough to drop the lamp power way down. This is a common feature.

Bottom line: 4000/10,000 for full power and eco mode respectively, is better than most. And should help deliver a low cost of ownership – never a bad thing!

Color Wheel and Rainbow Effect

color wheel photo
Photo of a generic RGBRGB six-segment color wheel, in this case with all "slices" the same size.

For the few of us who are sensitive to the RainBow Effect (RBE), the speed of the Optoma color wheel comes into play. Optoma puts a 2X color wheel in the UHD51A (and UHD50). This is on the slow side, and as a result, I do see rainbows on most fast action dark scenes, when bright white objects are moving… Fortunately for Optoma, only a small percent of people are RBE sensitive. (I’ve never seen published numbers, but I would guess between 5 and 10% of the population), and people vary in terms of how sensitive they are as well.

I’m typically RBE sensitive, so I can say that I would definitely prefer a faster color wheel (such as found with competing BenQ projectors). But for most folks this is a non- issue. If you don’t know if you are RBE sensitive – this is the first DLP projector you have looked at, be sure to purchase from some reputable AV dealer with a good exchange/refund program. If it turns out you are one of us RBE types, then this projector is probably not the best choice for you. There are competing projectors with faster color wheels, and 3LCD projectors (no RBE because no color wheel), as alternates.

BTW not the worst color wheel of late. I really liked the Acer laser projector, the VL78560. It has even more rainbows, so I couldn’t own it, but I can definitely recommend that more expensive projector for those not sensitive. Same for this Optoma except that the amount of rainbows isn’t too bad – the Acer much worse.

Bottom Line: If you are rainbow sensitive, you may still really like this projector, despite the occasional rainbows. Or you may want to look elsewhere. The best news, though, is you are probably not RBE sensitive anyway.