Pros & Cons
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- Ultra short throw (UST) lens throws a big picture at just inches from a screen or wall
- Highly portable
- Native resolution of 4K (3,840 by 2,160)
- Tricolor laser light source
- Solid image quality and brightness
- Streaming via LG webOS
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- No support for 3D output
LG CineBeam S 4K UHD Smart Triple Laser UST Projector PU615U Specs
| Dimensions (HWD) | 6.3 by 4.3 by 6.3 inches |
| Engine Type | DLP |
| Inputs and Interfaces | Bluetooth |
| Inputs and Interfaces | HDMI 2.0b |
| Inputs and Interfaces | USB 2.0 Type C |
| Inputs and Interfaces | Wi-Fi |
| Maximum Resolution | 3840 by 2160 @ 60Hz, HDR |
| Native Resolution | 3840 by 2160 using 1920 by 1080 DLP chip with XPR fast-switch pixel shifting |
| Rated Brightness | 500 |
| Warranty | 1 |
| Weight | 4.2 |
Compact ultra short throw (UST) models are uncommon in the projector world. Indeed, the LG CineBeam S 4K UHD Smart Triple Laser UST Projector PU615U is only the third we've reviewed, and, at $1,299.99 list price, the most expensive of them. The first model we tested is no longer available; the second, the 1080p (1,920-by-1,080) AAXA M8 UST, is the only model that comes close to being a direct competitor. (Other projectors in the same price range don't offer a UST lens.) The key reason for the CineBeam S's higher price compared with the M8 UST is its 4K resolution (3,840 by 2,160). But even if it were 1080p and priced accordingly, it would still score higher for image quality, thanks to other factors, including color accuracy. The high-quality image, plus the impressive overall design, are enough to make the CineBeam S our first Editors' Choice winner for a mini UST model.
Design: A Minimalist Box in Silver and Black
The CineBeam S offers a unique physical design for a projector. At 6.3 by 4.3 by 6.3 inches (HWD), it looks like a large box camera from the early 1900s or before. In this case, the lens is on top rather than at the front, and its 4.2-pound weight would make it a little heavy for a camera. Beyond that, LG's excellent fit and finish, along with its two-tone silver-and-black color scheme, add up to a sleek, stylish look.
What's inside the box is fairly typical. As with almost all 4K portables, the CineBeam S relies on a 1,920-by-1,080 DLP chip along with TI's XPR pixel shifting to generate its 4K image. And for its light source, it uses the increasingly popular choice of a tricolor red/green/blue laser light engine, which tends to offer a wider color gamut (that is, a larger range of colors) than other sources.
LG rates the coverage at 154% of DCI-P3. Note that BT.2020, the spec for UHD TVs and projectors, is about 140% of DCI-P3, so this implies a gamut that likely covers more than 100% of BT.2020. That assumes, however, that the extra 54% beyond DCI-P3 extends to the same area of the visible color gamut that BT.2020 covers. LG rates the laser lifetime at 20,000 hours and the brightness at 500 ANSI lumens.
(Credit: M. David Stone)Physical setup is straightforward, thanks in part to the projector's light weight, which makes it easy to position. The external AC power block plugs into one of the two USB Type-C ports on the back, leaving the other one free for connecting to a phone for wired mirroring or other video sources. The only other connection option is the one HDMI port. As with most portable projectors today, you can take advantage of auto-setup features for focus and for both vertical and horizontal keystone adjustment.
Autofocus worked reasonably well in my tests, but I sometimes found I could improve on it with manual adjustments using the remote. Keystone adjustment is best avoided if you can, since it can introduce artifacts; also, it lowers the brightness of any given-size image. I turned it off for my tests, instead relying on physical positioning to avoid keystone distortion.
(Credit: M. David Stone)Note also that LG includes a hard-to-miss warning that the auto keystone may not work well on uneven surfaces or at distances beyond about 15 inches. I confirmed in my testing that it worked far better at just a few inches (and smaller image sizes) than at 15 inches or more from the screen.
The built-in streaming, powered by LG webOS, doesn't require any significant setup beyond connecting to your Wi-Fi network. It's also easy to use, and it offers apps for most popular streaming services, including Amazon Prime, Apple TV, and Netflix.
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(Credit: M. David Stone)The two 4-watt speakers in the onboard stereo audio system delivered usable sound quality in my tests, along with high enough volume for a small to mid-size family room. On a scale from tinny to full-bodied, however, it was…not tinny, exactly, but closer to the low end of the scale than the high end. If you want better audio, you can connect to an external system using Bluetooth. LG even adds links on the CineBeam S web page to two of its portable Bluetooth speakers, so you can easily add either to your order. Unfortunately, it didn't provide either sound solution with the projector for testing.
Image Quality: In a Word, Impressive
The CineBeam S menus list eight picture modes for SDR input and another eight (with the same names, except for the "HDR" in the menu heading) for HDR10. (The projector also supports HLG.) All the modes offer a useful assortment of settings for adjusting picture quality, including basics such as contrast and brightness (listed as "Black Level" on the menu), as well as more sophisticated options like Dynamic Contrast and frame interpolation (dubbed "TruMotion" on the menu).
For SDR viewing in a dark room, I quickly settled on Cinema as my preferred mode. Other choices were brighter, but Cinema scored much higher than most for color accuracy, and the only setting that needed an adjustment was black level. The default setting was too low to preserve shadow detail. Setting it correctly solved that issue without washing out bright scenes, which let the projector score well across the board—for color accuracy, contrast, black level, and shadow detail.
(Credit: M. David Stone)For HDR input, the Cinema mode—or HDR Cinema mode, in this case—was once again my pick for best color accuracy. With default settings, however, scenes dominated by midtones were darker than they should be, which is a common issue with projectors that support HDR. I was able to improve it by turning on Dynamic Contrast and setting it to low, and nudging the black level up just a touch. After my changes, the HDR image quality was substantially the same for scenes we tested using the same movies on both SDR and HDR discs. Scenes dominated by midtones were still slightly darker than in the SDR versions, and the projector lost a little more shadow detail. But practically speaking, anyone who's not as familiar with our test material as I am probably wouldn't notice the difference without a side-by-side comparison.
As with any DLP-based tricolor laser projector, the CineBeam S can exhibit rainbow artifacts (red/green/blue flashes) and speckle. How easily you see either type of artifact varies tremendously from one person to the next, so if you're concerned about either, buy from a dealer that allows easy returns. As a point of reference, I saw the flashes more often than with many DLP models, and they were more obvious, but I didn't see any speckle. However, my eyes tend to see the rainbows easily and not see speckle.
(Credit: M. David Stone)Two issues that you may or may not care about are 3D support—the CineBeam S doesn't offer it—and input lag, an important issue for gaming. My Bodnar 4K Lag Tester measured the lag at 50.2 milliseconds for 1080p and 4K at 60Hz—short enough for casual gaming only.
LG rates the brightness at 500 ANSI lumens, which would make it bright enough to fill an 87-to-118-inch, 1.0 gain, 16:9 screen in a dark room. (You'd expect to see the highest image brightness at the smaller size.) In my tests using the lower-brightness Cinema mode, the image was roughly as bright as I would expect from about 375 lumens, which was still enough to light up my 90-inch screen. Overall, the image brightness was a bit lower than I prefer, but good enough. In low ambient light, with one floor lamp on, the image was watchable at that size, if a little washed out.
Final Thoughts
(Credit: M. David Stone)
LG CineBeam S 4K UHD Smart Triple Laser UST Projector PU615U
The LG CineBeam S 4K UHD is the best ultra short throw (UST) mini projector of the moment, delivering UST convenience, reasonable portability, solid 4K image quality, and a slick, minimalist design.