Gone are the days when projectors were only used for presentations; now you can watch movies on your wall and not compromise on quality, sound and space. So, when Acer asked me if I wanted to review the Acer K138ST DLP 3D capable projector, I quickly said yes as I wanted to view some of my favorite movies on a larger viewing area than my 44″ Vizio, and that area would be my bedroom wall.
Design And Features
The K138ST is a handsome projector, white with a flat top, curved sides, and rounded corners. It measures 2.3 by 9.4 by 5.8 inches (HWD), making it a little larger than palmtop size and smaller than the InFocus LightPro IN1146. It’s lightweight at 1.7 pounds, and it comes with a soft carrying case.
This DLP-based projector has native WXGA (1,280-by-800) resolution, a rated brightness of 800 ANSI lumens, and a 100,000:1 rated contrast ratio. Its LED light source is rated at 20,000 hours in Normal mode and 30,000 hours in Economy mode, so the bulb should easily last the lifetime of the projector. Its throw ratio of 0.8:1 is at the upper limit of what we would consider a short-throw projector. This lets you place the projector a bit closer to the screen for a given image side than a standard-throw model.
On top of the K138ST is a four-way controller with center button that you can use to access the menu system, as you can also do with the projector’s small remote. Behind the lens is a focus ring. As is the case with most short-throw; and most mini-projectors, it lacks an optical zoom.
One interesting feature is LumiSense, an ambient-light sensor that can adjust the projector’s brightness and color saturation based on local lighting conditions. It can be turned on or off from the projector’s menu.
You can project 3D content with the Acer K138ST, but you’ll need DLP-link active-shutter 3D glasses for each member of your audience. It’s not a great choice for 3D projection, however, as rainbow artifacts are visible in some 3D, as well as 2D, images.
The K138ST has a basic set of inputs, including a VGA port, and an HDMI port, which also supports MHL and lets you project content from your smartphone or tablet. There are also audio-in and audio-out jacks, and a port for a Kensington lock, a good protective measure for such a portable projector. Its USB Type A port is strictly for charging an external device like a phone, as was the case with the Acer C205. In comparison, the InFocus IN1146 adds an SD card slot, and its USB Type A port supports either a USB thumb drive or an optional Wi-Fi dongle.
Video And Audio Quality
In my video testing, rainbow artifacts were more obvious than is usual for a DLP projector, and would likely be distracting even to people mildly sensitive to the effect. I also noticed some posterization, a tendency for abrupt shifts in color or tone when they should be gradual. Because of these issues, I would limit video use with this projector to short clips, whether YouTube videos or as part of a presentation.
Sound from the Acer K138ST’s twin 3-watt speakers is good for use in a small room. If you turn the volume up more than halfway, you receive an onscreen warning telling you that over-boosting the volume can cause bad sound quality. If you want more volume or better audio, you can connect a set of powered external speakers to the audio-out jack.
Quiet And Cool
After running two long movies, I was pretty surprised when I was packing the K138ST into its trendy carry bag; immediately after the movie marathon; the projector was not hot at all! On top of that there was no fan noise, which is a great plus point when watching dramas with a lot of dialogue, or when doing a presentation where you don’t want to be annoyed or be an annoyance with a whirring sound on the background.
Bang For The Buck
After testing this projector out with some friends for the movie marathon, suddenly everyone wanted to buy one. The Acer K138ST is affordable, lightweight and it was so easy to setup you don’t need to be a tech junkie to do it. On top of that, the lifespan for this projector is slightly longer since it uses LED technology. Although it was not bright enough or super sharp, I think the pros outweighs the cons quite a fair bit.
The Acer K138ST is compact and easily portable, and it has a relatively short throw for an LED projector, so you can position it close to the screen or the wall, and you can also display content from a smartphone attached to its MHL-enabled HDMI port. Its brightness and sound system make it best for use in small rooms, and data-image quality is average, while video is best kept to short clips, mostly because of the rainbow effect. For the price of $799, there are probably other similar products out there, but for the build quality and everything, it’s hard to beat this price. Acer just makes really good, durable products and that’s important when paying a price like this for a product of any kind.