Projector Reviews Images

Optoma UHD51A 4K Home Theater Projector Review: Summary

Posted on July 29, 2018 by Art Feierman


Optoma UHD51A
Front view of the1.3:1 manual zoom lens. Focus ring on lens, zoom on top

In terms of performance the Optoma UHD51A is pretty typical of the 4K UHD projectors that are using the lower resolution 1920x1080x4 DLP chip. Where it separates itself from the pack at times is in other areas. First, of course it works with Alexa, making it smarter than any other 4K UHD projector under $2000 to date. True, Alexa doesn’t bring all that much to the party, at least not yet. You can power up and down, and if using the internal speakers, adjust the volume. Also you can control the built in 4K media player with Alexa. Still, Optoma can add far more capabilities by building out their Skill. The same should be true for their Google Assistant support.

The images above are a good example of the capabilities of this Optoma projector and it’s less expensive, but not as smart twin, the UHD50.

The first image is from 4K streaming off of Netflix, that’s followed by 3 4K movie images off of 4K Blu-ray UHD, and the rest are movie and HDTV/Sports at 1080p resolution or lower.

The UHD51A did come up short in brightness measurements, but was still about typical for any of these projectors with RGBRGB color wheels. (We report, the differences, but we care about the overall value and quality, not whether or not they hit a claim.  Optoma claims a bit more than most using the same chip (2200 or 2000 lumens are more common factory claims for RGBRGB color wheel projectors), so their slightly bigger miss I attribute to more enthusiasm by their marketing folks, than their competitors. In our Best/Dark calibrated mode the Optoma was less bright than expected, in the 800 lumen range, but that mode is for your 1080p movies, and maybe HDTV when you have the room darkened, and are watching high quality content like Game of Thrones.

Projector Reviews Hot Product Award

This is our top regular award for projectors. Best of Best Awards are given out in our reports.

Fortunately the projector measured over 1250 lumens in the calibrated HDR mode Eric created. While 800 lumens is easily enough in a home theater for a 130+ inch diagonal screen, one can never have enough lumens for HDR, so the extra about 50% helps. BTW my measuring device is 1080p not 4K. I have no way to tell if 4K has more lag, although I don't think one should assume that it would.

Gamers - The UHD51A is an OK gaming projector.  Using my Leo Bodnar Input Lag measuring device the Optoma consistently measures between 59 and 60 ms, mostly 59.7 it would seem. That makes it a bit slow, we consider the 50s to be just acceptable to most gamers. The hard core are looking for below 30 ms.  Over the years we've seen projectors as good as 16ms (one frame behind with 60fps games).  If you are the person who bought a low input lag monitor for your gaming computer, then this projector will likely seem too slow to you.

Again, the average gamer will be fine with it, but appreciate a touch less lag.

It’s nice that the UHD51A – and UHD50 – have Creative Frame interpolation for smooth motion for sports (for everyone), and also for other (non-movie) content on HDTV (for those who really like CFI on). Many DLP competitors lack it.

Overall, I like that Optoma has provided a modest amount of vertical lens shift.

The UHD51A and UHD50’s Competition

Vertical lens shift – a feature found on too few DLP projectors, (even if the amount provided when it is offered is minimal compared to 3LCD and LCoS projectors). Still, better than nothing, because if it helps, you don’t need keystone correction which damages picture quality. Because it is limited in range, you probably can’t rear shelf mount this projector up high. But then with only a 1.3:1 zoom you probably couldn’t place it in the very back of most rooms anyway.

I found the overall audible noise levels of the UHD51A to be acceptable. By comparison, I definitely wished for lower audible noise at full power when watching the BenQs and Viewsonic... So, give the Optoma(s) the advantage.

Brightness – as already stated, the UHD51A is overall typical. None of the other lamp based projectors using the same chip and an RGBRGB color wheel vary significantly in brightness from each other. (Well mostly they all come out of just two or three factories in Asia – we’ve previously discussed how one of the Viewsonic’s is nearly identical to one of the BenQs.

The Optoma though is the least bright in best mode, although it has more than enough brightness in a home theater environment for a pretty large screen. With HDR, the UHD51A does well enough, and is more typical. Once one leaves the world of 4K UHD DLP projectors and starts looking at other competition there’s more variation. The Epson HC4000 and HC5040UB are both more expensive (but measured in hundreds of dollars). Both are also pixel shifters using 1920x1080 chips but are x2, not x4, so they are 4K Content capable, but not officially 4K UHD.

Audible noise was unexpectedly quieter than I anticipated. With other projectors using the same DLP chip, I believed that when doing the 4x pixel shifting, that was adding a lot of hum like noise. This UHD51A howeve lacks that hum, or at least it’s a lot lower. So, either the problem is caused by the DLP chip, and Optoma’s slightly larger physical size may be allowing them to better mute that noise, or the hum on the other two brands of projectors is being caused by some other reason.

Short version: This is the quietest 4K UHD projector so far that we’ve had here, using the 1920x1080x4 chip. This is the 5th such projector using that chip to grace my theater. The others consist of two BenQs – the HT2550 and TK800, a Viewsonic – the PX727-4K, and the LG HU80K (which has a laser light engine and lists for $2999). That LG is our next review to publish – I haven’t really worked with the LG yet just long enough a few weeks ago to take some “right out of the box” photos of it in action using default settings. The LG may turn out to be quieter? But the Optomas are noticeably quieter than the others.

The Optoma will have the sight edge on sharpness with 4K content over those, and have at least as good black levels as the HC4000, but the HC5040UB is, as mentioned earlier, a real step up in performance in terms of black levels and handling really dark scenes. Also the two Epsons can muster up a brighter HDR image when calibrating Bright Cinema for HDR. When on those one calibrates their Best mode: Dark Cinema, then the Epsons are slightly brighter. With HDR though, you are looking at close to 50% more lumens from the Epsons, if my memory serves. Bright Cinema isn’t as accurate on the Epsons as their best calibrated mode, but considering the UHD51A’s calibration isn’t as tight as most, those Epsons in their brighter HDR mode are at least as good in terms of color.

Still you are paying more for those Epsons, at least $500/$600 more for the 5040UB. And they aren’t quite as sharp, although they can fake it rather wellwith some great image processing. Those Epsons, however, are truly loaded with features compared to any of these 4K UHD DLPs, with things like CFI, of course, but also a ton of lens shift, a 2.1:1 zoom lens (instead of 1.3:1) and lens memory for movie fans who want to buy a widescreen (movie shaped) screen instead of a 16:9 one.

Still the Optoma should have a slight advantage over the HC4000 in black level performance, while the 5040UB will easily best the Optoma at the same.

When comparing the UHD51 vs the Viewsonic and BenQs, I’ll start with the BenQ HT2550 which also has an RGBRGB wheel. Post all adjustments. the BenQ HT2550 wins in terms of the best overall color, but the Optoma which doesn’t calibrate as well, isn’t too far behind. You’ll be considering trade-offs such as how much lens shift and CFI (Optoma only) are worth to you and also lower audible noise – all favoring the Optoma. The BenQ HT2550 offers the slightly better color accuracy, plus about an extra 20% more lumens in HDR mode, and a faster color wheel with almost no rainbow effect visible to those of us RBE sensitive. The other advantage is that the BenQ sells for a good deal less, but then it isn’t smart – no Alexa or TV type smarts (no Netflix, Amazon apps etc.). Remember that Optoma’s UHD50 lacks Alexa, and wireless, but is $300 less list price in more directly the competitor for the BenQ.

Then let’s discuss briefly the Viewsonic PX727-4K which physically is obviously similar to the BenQ (every input in the back, the lens, the speaker – are all in exactly the same places), although the firmware is different. The Viewsonic doesn’t offer calibrated color as good as the BenQ, and perhaps not quite as good as the Optoma, but as Viewsonic did with the early 1080p home theater projectors, they have decided to be the price leader. The PX727-4K is simply the least expensive of these 4K UHD projectors, priced right around $1000 when Viewsonic is running promotions. So, not the best of the group, but the least expensive.

Other than those mentioned, and the more expensive LG I’m reviewing next, the other “competition” is not 4K capable. So, for example, the Sony HW45ES, at $1999, offers gorgeous skin tones, and has better color – unadjusted – right out of the box, than most of these others post calibration, is only 1080p, it has no 4K capabilities at all, but it has lots of lens shift, far more zoom range, and plenty of features.

Finally your other choices –also not 4K capable, consist of Epson’s lower cost 2100 and 2150 ($800 or less) and DLP 1080p projectors – also mostly under $800. So, while to plan for now and the future, you should go 4K capable at least, if the budget allows, know that you can spend about half as much and get a dumb Optoma but one similar in feature set but only straight 1080p.

Bottom line, are the competition. Choose wisely. Since many of these projectors are very similar, figure out the important things for you – the quieter projector, the lens shift, don’t forget the warranty which can vary a lot on these various projectors that are 4K capable, from 1 year, to 3 years, and some have overnight (or two business day) replacement programs. Certainly the UHD51A is one of the strongest of these, in features but when it comes to value, it is also the most expensive of these lamp based DLPs.

Let’s also not forget the more expensive DLP chip. If you have the extra $500 or so you can opt for the UHD65 using the larger better chip (2716x1528x2). But even then look to other differences, since the sharpness difference is extremely slight.

Of all the 4K UHD DLPs only the Acer VL7860 had excellent black level performance, but it is laser based and sells for about double the price.

The Very Bottom Line on the Optoma UHD51A

At $1699 list price, and Alexa support it’s a really interesting projector. I do like the Alexa support but without more voice controlled capabilities in their Skills it’s hardly worth the $300 more over the UHD50. OK make that $200, since you also get wireless, which isn’t an option on the UHD50 (but it is available on most of the 4K UHD projectors as an option.)

Streaming 4K!  Blacklist using Netflix
Streaming 4K! Blacklist using Netflix

If the bucks are tight, obviously the UHD50 provides more value, unless you definitely need the wireless. When comparing with the others, its going to be price vs features as well. Truth is, you really can’t go wrong with any of these, because, once properly set up, they will all look pretty great (except for lacking great black levels which requires a bigger spend. Still I thought the UHD51A’s black levels to be slightly better than, say, the BenQ HT2550.

Count the UHD51A as one of the best sub $2000 4K capable projectors on the market. If the features and other trade-offs align, it will be your best choice for the money. The UHD51A only lacks a significant improvement in black levels, from being a true stand out. If you are a hard core enthusiast with a decent cave or home theater, your biq question will be to stick with this Optoma (or another 4K UHD more suitable) in the lower price ranges, or spend from many hundreds to thousands more for 4K capable projectors that have serious black level performance.

Despite my disappointment with black levels, I found the UHD51A to be most watchable. And while I found the BenQs and Viewsonic a but too hum like noisy for my viewing pleasure, not so this Optoma.

The UHD51A definitely earns a Hot Product Award. And considering that the UHD50 lacks smarts and wireless, but offers, otherwise, even more value due to the $300 lower price, the UHD51A will share the award. Nikki will be creating a separate page or two on the UHD50, further defining the differences, and providing more value observations, and links back to this longer review of the 51A.


  • 4K UHD resolution (1920x1080x4 DLP chip)
    • 4K content capable, including HDR10
    • lower resolution of the two 4K UHD DLP chips, but nicely sharp
  • First projector to work with Alexa (won't be the last) and Google Assistant
    • Works well enough but limited capabilities - so far
    • Expect more
  • RGBRGB color wheel for home "theater" quality color
  • Just over 1250 usable lumens for HDR which is pretty good for one with "theater" chip
  • Over 900 lumens for best mode, fine for 1080p movies, larger screens
  • Dynamic Black lamp dimming enhances black level performance
  • Very good dark shadow detail
  • Built in media player, which supports images, videos Microsoft office and more
    • Alexa can control some of the media player features but I'm told more Alexa support coming
  • Projector is end user firmware upgradable.  (should be OTA - over the air - aka wifi).
  • CFI for smooth motion
  • Speakers built in so projector can easily be moved from room to room, outside
    • Still, get a real sound system
  • Handles HDR rather well with limited "dimness"
  • Some very good modes right out of the box, but definitely better post calibration
    • Try our settings...
  • Lens shift - not a lot, but could be a real plus for you setup
  • Quieter than some of the direct competition
  • Two year parts and labor warranty - not bad, better than some


  • Black levels could be much better
    • Better than much of the DLP competition though
  • A bit low on brightness vs claim.  Claim: 2400, max we measured 1982 lumens
  • I prefer remotes to be backlit - helps when lights are out
  • Warranty could be longer - 2 years, but BenQ and Viewsonic competitors have 3 years
  • Could be quieter in full power
  • Could have more zoom range and lens shift
  • $300 more List price, than HD50 - for which mostly you get Alexa and wireless capabilities.
    • Is that too much to pay?  (A question only you can answer).

Latest Reviews

February 25, 2024

Introducing the Hisense C1: A cube-shaped 4K UHD lifestyle projector with an RGB triple laser light source and integrated JBL ...

February 19, 2024

The BenQ X3100i is a 4LED, 4K UHD (3,840 x 2,160p) 0.65" DLP short-throw gaming projector that offers a BenQ-rated ...

© 2024 Projector Reviews

crossmenu linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram