Optoma GT720 review

DLP gaming projector with novel 3D option
Photo of Optoma GT720

Do we need 3D? Consumers seem pretty confused about the latest in-yer-face technology – and with new 3DTVs costing around the £1,000 mark, that confusion isn’t the only barrier to its popularity outside of multiplex cinemas. Optoma obviously realises this. How else can we explain its decision to make 3D an accessory to its GT720 ‘GameTime’ projector, rather than an integral feature?

Big picture
But before we delve into the third dimension, consider the GT720 itself. For some, this projector’s appeal will revolve around its ability to throw a huge 120-inch image from a mere two metres away, something that makes it ideal for using in small rooms.

And it gets better; the Optoma’s bulbous lens projects upwards, so the GT720 can quite happily create a 60-70in image from a coffee table positioned under a screen (or wall), and around a metre away.

There is, however, neither zoom nor any fancy vertical and horizontal lens shift levers that would make positioning the product so much easier.

If that short-throw lens is a rare trait, it’s also the end of the GT720′s special skills, save for two 5W stereo speakers that actually do a thoroughly decent job with games.

The Optoma’s rear sports a sole HDMI input, plus connections for S-Video, composite and a dual VGA/component jack.

Unfortunately, though, when the GT720 looks for an input from one of these live sources, it’s often unsuccessful – and it’s difficult to give it a helping hand, as the tiny remote’s dedicated buttons for each source don’t appear to work. Nor does the remote have any useful backlighting for when you’re operating the GT720 in a blackout.

And when it comes to the picture, all isn’t entirely rosy. The pixel grid was visible in the 80in image we projected in our tests. Horizontal lines in particular were distracting. Less irksome was the fan noise, which is kept to a minimum.

Although easily bright enough – officially, it’s rated at 2500 lumens (though less than half that for 3D) – for daylight gaming, the GT720′s image appears soft at big image sizes. And it’s capable of a showing only 720p HD footage from its 1280×800 pixel resolution.

Colour is reasonably accurate, and we do like the Optoma’s automatic ViewMatch colour mode (which considers the source and switches the ‘mode’ accordingly), though it doesn’t always get things right.

In cinema mode, the GT720 is fit for purpose and makes discs watchable, while the games preset boosts brightness to deliver blur-free, if unremarkable, performance. We didn’t notice any ‘rainbow’ effect during gaming (despite being prone to it), though, and from a Blu-ray player it was only a slight problem.

Third way
Although the GT720 can natively handle 3D PC games that use Nvidia 3D Vision tech, it takes Optoma’s add-on 3D-XL processor/adaptor (£249.99, including a pair of 3D specs) to act as a conduit between other 3D sources such as a PlayStation3, 3D Blu-ray player or 3D-ready set-top box (from Sky or Virgin Media).
In effect, this add-on device takes the various 3D formats and converts them to the simple frame-sequential system for this – or any other – 3D-ready projector.

The box itself has two HDMI inputs, and one output to hook-up to the GT720. It’s small enough not to be much of a pain to house – it could easily slip underneath the projector. Similarly well designed is the pair of ZD201 Active 3D glasses supplied, which are lighter, cheaper and simpler than those that ship with 3DTVs, but heavy enough at the front to keep them in position.

The GT720, as with all 3D projectors at this low end of the market, churns out frames at 120Hz. Technically that refresh rate should be fast enough for 3D, but in practice the picture is not so simple, due to significant differences in the maths.

Not only are all 3D sources delivered at different frame rates (3D Blu-ray is delivered at 24 frames per second, which multiplies up to 96Hz – that’s 48Hz to each eye – while Sky 3D broadcasts equate to a maximum of 100Hz), but the 3D-XL is also designed to convert from both the 3D Blu-ray and side-by-side broadcast 3D standard. In the unforgiving frame-sequential 3D format that the GT720 uses, some 3D footage excels – and some is impossible to watch.

Wipeout 3D from a PlayStation3 looks good, though the more subtle Gran Turismo suffers from crosstalk flicker and some annoying motion artefacts. It’s a similar tale from a blast of live action 3D from a Virgin Media set-top box. This looked a confused mess with backgrounds and foregrounds difficult to decipher, while an animated trailer of <i>Despicable Me 3D</i> from the same source appeared pitch-perfect. Annoyingly, there’s no remote for the 3D-XL to engage the ‘SBS’ switch for side-by-side 3DTV footage.

Company: Optoma

Website: http://www.optoma.co.uk/

Contact: Optoma on 01923 691800

  • 2D brightness; short-throw lens, relatively low-cost 3D add-on.
  • Tricky to position; 720p limit for HD and 3D; inconsistent 3D effects.


The Optoma GT720 is a reasonably impressive 2D projector that's versatile enough for most uses, and does appear good value as a standalone product - particularly for use with a games console. Our conclusion from its 3D performance, with the 3D-XL processor in tow, is that the various 3D formats mean significant highs and lows.
The more subtle the 3D effect, the more problems appear - though there's no doubting that the GT720 is a fine budget 3D projector when given the chance. One for gamers with an eye on the 3D future.