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Optoma UHD51A 4K UHD Smart Home Theater Projector
Audio/Video Reviews

Optoma UHD51A 4K UHD Smart Home Theater Projector

Optoma brings out their most comprehensive home entertainment 4K DLP projector yet, they also included Amazon Alexa voice functionality.

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Throughout my tech stint I’ve covered as many projectors as manufacturers would let me get my hands on. with 2018 being a watershed year for affordable 4K home entertainment DLPs, I’ve been impressed—short of enthusiast options that cost thousands more and employ sophisticated LCoS/OLED image processing.

Each one I’ve been able to review has been better than the last starting with ViewSonic, then BenQ, and now I finally get to the Optoma UHD51A 4K DLP Projector. This a quasi-flagship for savvy consumers who demand the best and biggest 4K and HDR display beyond the now-normalized 60-75 inch TV sizes; but also a financially viable home theater arrangement. Obviously, the $1699 MSRP for the UHD51A is well below the $2000 threshold, and is the first projector to include voice-activation and assistance through Amazon Alexa.

Clean Appearance

I’ll get to that in a moment but let’s go over the external details first. The UHD51A sports a newer and more practical 11.75lb body that’s ridged for venting with an absolute minimum of styling flair. The construction is largely black plastic with a silver-painted wraparound strip that breaks up the top and bottom halves. You have the usual array of top-mounted menu controls and manual projection adjustments for focus, 1.3x zoom, and integrated vertical lens shift—the latter of which is an incredibly convenient function over keystone adjusting, and a general rarity for most projectors in this price range.

The remote is equally passable, if uninspired with the necessary volume, source, and menu shortcuts available. Its thin and uses a lithium-ion battery to save weight and expense, if you’ve seen previous Optoma remotes then this won’t be anything amazing to you.

Move to the back and I/O connectivity is seemingly also-ran, incorporating two HDMI ports, VGA/component, LAN, 3.5mm stereo input, 3.5mm stereo output, S/PDIF optical audio, 12V trigger, and RS-232 (for installer control. There are a staggering number of four USB ports that each have a specific use: Wireless dongle for Amazon Echo, wireless dongle for mobile device/version 3.0 for media playback/firmware and service. The HDMI on the UHD51A are also noteworthy because they are both 2.0-spec and utilize hardware HDCP v2.2 encryption for proper 4K/HDR compatibility, so you don’t to keep switching out gear if you haven’t picked up a capable AVR or soundbar yet.

XPR by Texas Instruments

I’ve already touched on this for prior 4K DLP reviews, but the Uptoma UHD51A incorporates a smaller 0.47-inch DLP470TE XPR DMD chip from Texas Instruments. With active micromirrors multiplying an 1920×1080 image four times over, this projector essentially produces 8.3 million pixels and proper HDR without the burden of higher production cost. Of course, this means the consumer benefits as well.


Overall picture quality is among the best compared to other DLP projectors recently tested. Color performance out of the box appeared accurate with no visible evidence of warm or cool tinges in hues, which is a nice surprise considering that I normally have to adjust temperature hues almost immediately. The UHD51A for most intents was calibrated and balanced just right for people who loathe diving into the overwhelming color setting. A lot of the praise can be attributed to the new RGBRGB color wheel, improving color accuracy and greatly reducing the dreaded ‘rainbow artifacts’ commonly exhibited in more sensitive eyes.

There are the usual ‘Cinema’, ‘Game’, ‘Reference’, ‘User’ and ‘HDR SIM’ to play with. Each one has their purpose and customizable to an extent with some falling on greenish tints, but a lot of this will come down to preference full-on adjustments are too daunting.

This contributes to excellent HDR performance as well, with four mode presets and automatic switching to SDR based on the content presented. The BenQ TK800 handled these tasks well enough, but Optoma does a much better job with individual ‘Bright’, ‘Standard’, ‘Fil’, and ‘Detail’ modes. Each preset handle dimension and contrast nicely in their own way, the notable difference between them is overall brightness with each making the image darker and reduced separation of shadow details.

The HDR options are relatively minor tradeoffs solely focused making hues pop better, I left it on ‘Standard’ but this could be unconventionally used in to keep ambient light in check for daytime viewing, or to further dial in certain content in terms of atmosphere. Once again at these cheaper projectors, gamut formats such as Hybrid Log Gamma (HLG) and Dolby Vision are absent.

Other technical features of the UHD51A include an ANSI 2400 standard lumen count (optimized ANSI 1685 SDR/1960 HDR observed), and good brightness uniformity with indistinguishable side fading to the naked eye at 80%. The lamp should has an expected lifetime of 4000 hours if you exclusively opt for Bright lighting, and much longer in ECO or Dynamic modes (10000/15000 hours respectively) which I strongly recommend since replacement bulbs cost $200 apiece. Although the lower lamp modes lower brightness by 33%, it has a unintended advantage of giving images the illusion of deeper colors in dark rooms, and keeps the UHD51A fan noise in check at 24dB versus the regular 28-32dB.

In My Eyes: UHD51A

The UHD51A is by far the best and fully-featured DLP I have currently tested for Popzara. The closest competitor is the BenQ TK800 and that’s already a great projector for what it is, but Optoma gains the edge through small performance advantages. The black levels though minute are deeper helping the overall picture pop with improved natural presentation in movies and welcome vibrancy for gaming. The majority of my testing was done with a PC (AMD Ryzen 1800X desktop CPU, GIGABYTE GeForce RTX 2070 GAMING OC, Pioneer BDR-211UBK Blu-ray drive), Apple TV 4K, and a PlayStation 4 console. I chose to watch material measured at 118 inches and a 9 foot floor placement throw distance.

With Far Cry 5, Final Fantasy XV, Shadow of the Tomb Raider, Forza Horizon 4 and Horizon: Zero Dawn each game made good use of either increased resolution (2560×1400/QHD or 3840×2160/4K) or the additional color range provided through HDR, though the input lag of 64ms (milliseconds) is average. Shows and films viewed through Netflix/Hulu/Amazon Video are accurately portrayed with general quality corrected by color and shadow contrast no longer appearing muddy or blocky against most SDR content. Prime examples I noticed were on Altered Carbon and The Grand Tour, but Ultra HD Blu-rays proved to be the best option with The LEGO Batman Movie and Black Panther.

Stereoscopic 3D (frame packing/side-by-side/top-bottom) is also possible with the UHD51A, so you’re not left in the dark if you’ve got a library of 3D Blu-rays, it looks good with no trace of crosstalk and only a mild drop in brightness and requiring DLP-Link active-shutter glasses only.

So, is there anything that I don’t like about the UHD51A? Yes, mainly the PureMotion (aka frame refresh interpolation). Like HDTVs before it, PureMotion tries to  eliminate judder or smoothing the picture especially in moving shots, unfortunately which has the unsavory effect of making video look like a cheap soap opera—and ruins movies to a tee. The silver lining are the dual 5W speakers can easily fill up a medium room or apartment without sounding tinny or flat.

Amazon Alexa: Best Left Unsaid

The Alexa (and Google Assistant) voice functionality is supposed to be a defining feature for the UHD51A but feels more like a gimmick than anything else, specifically turning the projector on/off, change the volume, and control playback in the USB media player. My biggest criticism is that the initial setup is a bit of a pain with you needing to enable the ‘Full Power Active’ mode on the projector itself and putting the included USB Wi-Fi adapter into the proper port, and then connecting to your network. But the annoyance comes when your required to create and verify a separate Optoma MyDevices Cloud account, and then obtaining the ‘Optoma SmartProjection for Smart Home’ in the Alexa Skill Store (via Alexa app for Android/iOS) on top of your existing Amazon account.

You can already guess how cumbersome this is to set up because sometimes have to repeat steps or voice commands, even if you decide (for whatever reason) to change the projector name in the Alexa app. When everything is up and running it does work but fairly limited than just picking up the remote. You have to first tell Assistant to “talk to Optoma SmartProject,” then you can say something like “change display mode” or “change input to HDMI2” by the name you chose on Optoma’s website every time. I guess the best way to describe the smart home voice ability is that they work marginally but are inconsequential to the value of this projector.


The Optoma UHD51A 4K DLP Projector packs in whatever popular feature it can for excellent value, and it generally succeeds as far as intermediate AV goes. On that basis, this is an awesome large-format picture that I’ve come to expect from a home entertainment DLP, with 4K and HDR10 pushing it into top tier. Even though it is less than $2000 though, the UHD51A is still more expensive within this category, but not egregiously.

I’m sure they also wanted Amazon Alexa and/or Google integration to be the crown jewel. However, the novelty of voice commands simply don’t add much to warrant praise, and barely justifies itself in making your dwelling “smart”. That said, everything else about the UHD51A is a winner, and probably the best front projector I’ve reviewed for Popzara this year. If you can splurge on the extra $100-$300 this is the one to own.

About the Author: Herman Exum