Short throw lenses on projectors are rather popular at the moment, with an increasing number of models appearing, including from Acer, a brand best known for computer products, with its H7550ST. Stephen Dawson investigates.

Even though a carry bag is included, that the Acer H7550ST projector is directed towards home entertainment rather than business purposes is made clear by the support for 3D, including the provision of two sets of active eyewear. And it offers, of course, a full high definition display.

The engine is based around a single Digital Micromirror Device. It is rated at 3,000 ANSI lumens output, or 2,400 in the reduced output ‘Eco’ mode. The contrast ratio is rated at 10,000:1. The minimum life expectancy for the lamp is an impressive 4,000 hours. This increases by 50% in Eco mode, and doubles for something called ‘ExtremeEco’. This one lowers the lamp output by 70% during times of no signal, so its effectiveness depends very much on the usage style.

No lens shift adjustment is provided. There are adjustable legs to tilt the projector and keystone can be set to correct automatically or be adjusted manually. As always I strongly recommend against this. Put the projector in the right position so keystone adjustment’s reduction of picture resolution is unnecessary.

This truly is a short throw projector. The modest 1.1:1 zoom requires the projector to be placed at a range of between 1.5m and 1.7m in order to produce a 100” (2.54m) picture. The zoom and focus are adjusted by means of recessed lens rings which operate smoothly but are well protected from being dislodged. The usual installation options for ceiling mounting and reversing the picture rear projection are provided.

The projector contains its light well, with no leakage which could interfere with picture quality.

Three HDMI inputs (one is hidden, see below) are provided, along with composite, component and even S-Video. Analogue computer video is supported by a D-SUB15 socket, and can be passed through the projector to an output so another display can be daisy-chained. Also with ins and outs is audio, with 3.5mm sockets for both. The audio can be fed via HDMI as well. Two speakers are built in with 10W of power available for each. In addition, the projector supports connection to Bluetooth speakers.

Control is via RS-232C and USB. There’s a USB-style 5V power output which can be used for charging the 3D glasses.

A smallish remote control is provided. This was generally okay in use, and had enough power to bounce its IR beam off the screen and back to the projector. But changing sources was a pain. There aren’t dedicated input keys. Instead you have to use the ‘Source’ key and arrow to the input you want. And be quick about it. If you hesitate for two seconds – exactly two seconds, I timed it – at any point the selection menu disappears and whatever input you left highlighted is selected. I could find no menu option for lengthening this. The regular menu disappears after ten seconds of no interaction. Again, there’s no apparent way of increasing this.

Picture Quality

The picture quality produced by this projector was really quite good. The geometry was almost perfect, with just a few millimetres of bulge at the centre top of the screen, the cost of such a short throw lens. On regular program material this was not visible.

The black levels were good, if not brilliant. Late night viewing didn’t deliver a sense of velvety blackness in the dark areas of the screen, but neither did the blacks seem deficient. Colours were fairly accurate, and nicely rich.

Initially I thought the projector lacked a ‘Sharpness’ control, which is something I would not mourn. But it has the image processing split between two screens. This control turned out to be up quite high by default, yet did far less damage than most sharpness controls. I played with it a bit. Even at the highest setting it does not introduce the ‘ringing’ or ‘ghosting’ normally created by these things. Instead all it does is what its name suggests: it sharpens up the edges of pictures. It does such a good job that I’d be tempted to have it set to about 25%, rather than all the way off as is my usual practice.

I wish Acer would tell the major TV makers how to do this.

The unit incorporates decent motion adaptive progressive scan conversion for dealing with interlaced video, mostly getting my DVD test clips right, and lapsing from film to video mode in fewer ambiguous difficult spots than most. DVDs looked pretty good with this projector.

Since there isn’t any motion smoothing processing, the projector is quick smart in getting the image from input to screen. The latency measured at just 33.6ms, which is about as fast as they come these days. Gamers will find themselves getting good scores on games where reaction time counts.

There really isn’t anything to be said about the 3D performance of this projector, other than that it is about as close to perfection as you’re likely to see anywhere. Oh, if I wanted to quibble a little, I’d like it a touch brighter. Nonetheless, as you’d expect with DLP there was no ghosting at all, so the 3D was clean and enjoyable. The 3D glasses are white and silver for an … interesting, I guess … look, but they are light in weight and work well. They sync to the projector via an IR beam the projector bounces from the screen.

Wirelessness

One of the particularly interesting things about this projector is its extra-cost wireless options. There are two, so you will need to decide which you want. The less interesting one is WirelessHD, which is the ability to send full HD quality from your system to projector without the need for a HDMI cable. This system has been around a couple of years on a couple of different brands, and can be quite useful in some installations.

What I found more interesting – in part because the $149 wireless adaptor dongle was supplied with the review projector – is the wireless casting capability. Actually, at first I queried whether the dongle had been lost because it wasn’t in the box. But it has already been ‘invisibly’ installed. There’s a third HDMI socket inside the unit for the addition of the wireless capabilities. This is MHL enhanced (i.e. it can supply power to the plugged-in device).

So what can you do with this? First, puzzle it out. The instructions were extremely light on. I downloaded the Acer eDisplay Pro apps to an iPad Mini, a Samsung Galaxy 3 tablet and an LG Optimus G phone. The app didn’t seem to like the iPad Mini, and took to crashing during startup every time. But it worked fine on the Android devices.

However the dongle started up with a fixed IP address, disclosed by the splash screen when the WiFi input was selected. That made at least one of the capabilities of the app – the mirroring of Web browsing on the device – impossible because to use the WiFi dongle it had to be used as the wireless access point, rather than the router. On a hunch I typed the fixed IP address into a browser on the connected tablet and this opened up a configuration page in the dongle, so I was able to connect it to one of my wireless access points, and after a couple of false starts, access it via the app through its new IP address.

Of course, if you’re out and about the ability to connect directly to the projector without a host network would be invaluable. Still, I mention this so you’ll know what to do.

This is an extremely powerful function. The app opens up with selection of things that you can send to the projector: photos, music, video, the web browser contents, cloud video, your own cloud content and the camera. Your device’s camera can be routed wirelessly directly to the projector – very useful for presentations where you need to show live things on the big screen. The cloud function worked nicely with my Dropbox contents. The documents supported included PDFs, Word and Excel, but oddly not plain text.

The web browser function is fancy, too. Obviously it displays whatever the browser is showing, but it also has a ‘sketch’ function so that you can mark up web content live on the screen.

One other function is ‘Split Screen’. This lets you divide the screen up into two – side by side – or into four quadrants. Separate material from separate devices can be sent to each section. I used this with a tablet and phone in the side-by-side mode, and it worked exactly as advertised. The limitation is that you can’t stream video or music in this mode, but photos, documents and the web browser display all work well.

The sound, incidentally, was not particularly exciting, but it was loud enough for effective presentations in classroom-sized venues. If you want more sound, plug some active speakers into the audio output, or connect the projector to a Bluetooth speaker. The level was a bit quieter going via WiFi from tablet to projector and then via Bluetooth to speaker than it was going directly from tablet to the same speaker via Bluetooth, even with all the volume levels maxed out.

Conclusion

The Acer H7550ST is actually a decent basic home theatre projector with some rather nifty features and, given the two sets of 3D glasses provided, an excellent price.