Projector Reviews Images

Optoma UHD51A A Smart 4K UHD Home Theater Projector Review - With Alexa

Posted on July 29, 2018 by Art Feierman

Optoma – with its brand new UHD51A 4K UHD projector, is one of the first projector manufacturers to offer up a smart projector design for the mainstream of the market. This projector is 4K capable using the the smaller/less expensive of the two 4K UHD resolution DLP chips.

The secret sauce – if you will, the smarts – is supporting Alexa (and also Goggle Assistant) which I’ll go into at length in this review. Optoma put their “home theater” color wheel in this projector, but still manages to claim 2400 lumens, more than other 4K UHD projectors with similar wheels. (Hint, the UHD51A did not meet its brightness claim, but is comparable to the competition).

The UHD51A is $1699 list price, be aware, also that it has an almost identical twin, the UHD50, this is only $1399. With the UHD51A, it’s those smarts that you are paying for, with the difference in list price. (I suspect the selling prices will be closer to each other).

Projector Reviews Hot Product Award
Optoma UHD51A Specs
Price $3199
Technology DLP
Native Resolution 3840x2160
Brightness (Manufacturer Claim) 2400
Contrast 500,000:1, 500000:1
Zoom Lens Ratio 1.30:1
Lens Shift No
Lamp Life 4000 hours
Weight 11.8
Warranty 2 years


Meantime, with the UHD51A, you should expect a very sharp image on 1080p and lower resolution content, and even sharper with 4K content. There is little difference in sharpness at normal seating distances between projectors using the two different chips, and they are all very close in sharpness to the least expensive true 4K projectors (but not high end ones). In the world of more expensive lenses (lenses costing a lot more than this projector), you might buy a little more sharpness, but you also get more clarity – a clearer image (as if a film was removed from in front of the image).

The feature set is better almost all of the other 4K UHD DLPs in the price range, but that’s fair, as it is one of the most expensive using the 1920x1080x4 pixel shifting chip.

The difference between the two relates to the smarts and Wifi. The UHD51A comes with the wireless module which is not available for the UHD50. So you are getting the smart tech, and the wireless to make it work. And of course the wireless has other uses besides Alexa... If you don’t need the fancy, the UHD50 will save you enough money for a very good 4K Blu-ray UHD player, or a couple of years of Netflix subscription.

3D and smooth motion – a.k.a. Creative Frame Interpolation are both found on the UHD51A, add the WiFi to that, and the modest amount of lens shift, and without looking further, you have the best equipped of the 4K UHD DLP projectors (that using the smaller, less expensive chip). Now I would have loved to see a good dynamic iris, but you can’t have everything at this price point, considering this is the pricing range for “entry level” 4K content capable projectors.

The images in this player start out with some 4K content from Blu-ray UHD movies (Passengers, Ghostbusters, Journey To Space, followed by some 1080p and 1080i content (movies and HDTV). The last image is 4K content streamed from Netflix (Red from The Blacklist), which looks great in 4K although not HDR content.

approaching Mars

4K content from Journey To Space - stunning approaching Mars

Still a very impressive projector from Optoma so let’s get this review moving forward with the quick list of Highlights, then the Special Features... -art


    • 4K UHD resolution (the smaller, of the two DLP chips)
      Large pixels, but achieves 4K UHD by pixel shifting: 1920x1080 x4
    • Supports HDR (high dynamic range), and larger color space
    • Smart – Alexa compatible – Google Assistant too
    • 2400 claimed lumens with a “home theater” RGBRGB color wheel
    • 1.3:1 manual zoom lens
    • Comes with Wifi module (plugs into one of the 3 USB ports
    • Modest amount of lens shift (15%)
    • CFI for smooth motion
    • Built in speakers (5 watt x 2)
    • 3D
    • Built in media player plays 4K videos
      • Control slideshow using Alexa commands
    • For those not needing Wifi or Alexa type smarts you can
      • Save with the lower cost UHD50

© 2024 Projector Reviews

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