Optoma UHD51A 4K Home Theater Projector Review: Hardware

Posted on July 29, 2018 by Art Feierman

Overview

The UHD51A is slightly larger than some other DLPs (Optoma, Viewsonic...) using the same 1920x1080 x 4 pixel shifting chip, but then it also offers lens shift

There are three USBs on the UHD51A (the UHD50 lacks the one for the Wifi module. This USB is for feeding photos and videos (up to 4K) to the media player.

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The UHD51A is a smallish home entertainment projector, although it is just a bit larger than some of the 4K UHD competition from Viewsonic and BenQ that use the same DLP chip. Perhaps the cabinet is why it seems quieter than those others. The lens is manual, and offset slightly. There’s also an IR sensor for the remote control in the front, and below a single screw thread adjustable front foot. There are two rear feet, also both screw thread adjustable. For those not ceiling mounting, I find that to be the best possible adjustable feet arrangement, fastest and easiest to get level.

The zoom and lens shift controls are on the top of the UHD51A, as is the control panel. All the inputs and other connectors are located on the back of the projector.

The Lens

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

The 1.3:1 manual zoom lens provides a basic amount of placement flexibility. Still it provides a bit more than some competitors with merely 1.2:1 zooms. Still for not much more money 2.1:1 zoom lens show up on 4K capable projectors, for those needing more flexibility. I should note that the projector comes with a tethered lens cap.

To focus the UHD51A, just turn the lens barrel in the front. The zoom control, however is located on the top right behind the barrel. Unlike many inexpensive projectors, the lens mechanisms work smoothly. The zoom and focus do not affect each other. It’s always annoying setting up on a table, when you adjust the zoom, it goes out of focus, making it hard to get the zoom just right, so you have to mess with it a couple/few times. Not with this Optoma.

Lens Throw and Lens Shift

For a 100 inch diagonal 16:9 (HDTV) screen:
The closest placement of the projector (measured from the front of the lens to the screen) is 8 feet 9 inches. The furthest placement is 11 feet, 6 inches.

The vertical lens shift control is just behind the zoom control. It allows 15% of shift. That should add up to less than 7.5 inches of total shift, when using a 100” 16:9 screen. The manual, however does not provide specific numbers. A quick eyeballing of the range while putting up about a 96” diagonal image, looks to be a little more than 6 inches, so I’ll say “close enough”. Again, that’s very little, if ceiling mounting puts the center of the lens only a few inches above or below the top of the screen surface, or anywhere in between. By comparison most 3LCD and LCoS projectors with lens shift, thanks to the very different design of 3 “chip” devices, offer far more lens shift – 80% is not uncommon. By comparison a $2000 Epson or Sony can be placed anywhere from about 15 – 20 inches above the top of the screen, to the same amounts below the bottom – and everywhere in between.

Bottom line, the small amount of Lens shift can definitely help but won’t provide near the flexibility that some folks need, such as having to place the projector well above the top of the screen or on a table well below the bottom. On the positive side, most of the UHD51A’s competition offer no lens shift at all.

UHD51A Projector's Inputs and Connectors

When it comes to inputs, the UHD51A is particularly well endowed. That's in part due to being smart, and having Wifi, but also an extra input or two compared to some others.

From the back left side:

First up is a RJ45 jack for hard wired networking (CAT6 cable etc, "ethernet". Just over to the right is an RS232 serial port for "old school" command and control. Below it, is the first of three USB ports, this one is for the included Wireless (wifi) module. (The UHD50 lacks this input.)

A pair of HDMI inputs 1 & 2, come next. Both are HDMI 2.0 with HDCP 2.2 copy protection. That's what's needed for 4K Blu-ray UHD and other 4K sources using copy protection. Some competitors provide only one new HDMI, and one older, legacy 1.4 HDMI. The reason for that is to provide backwards compatibility, as the newer port may not aways work perfectly with some very old HDMI devices that are HDMI 1.4 or earlier. That said, I have several such devices and I haven't encountered any issues myself, with feeding my devices through an HDMI 2.0...

OK, let's get back on track. After the pair of HDMIs (a third is a great idea for those not using an AV receiver for switching, but few projectors offer 3.

Next up is a traditional analog computer input that can also accept component video (like most VGA inputs). The connector is the standard HD15 type.

Moving right along, there's a 12 volt trigger for a motorized screen, shades, or lens sled.

The Optoma does have that pair of 5 watt speakers, so no surprise that there's a stereo audio input and a stereo audio output. Then comes two more USB ports one labeled for Reader - for the media player, and the other with a wireless symbol.

Wait there's a fourth USB as well, but that one is a service port, so you won't be using. We didn't need to use the service port for the firmware upgrades I did.

Finally, below that USB is a optical digital audio connector as well. Now that's a nice extra touch, that provides some versatility. That folks is it for the inputs, although there's also the power cord receptacle, a Kensington lock slot below the left side connectors.

Bottom line: As I said, a nice collection. A lot of projectors are getting pretty minimalistic, with only a couple of HDMIs and 2-3 other connectors. Optoma's dropped composite video and S-video, like many others but at least still offers the VGA input, and plenty of USBs.