Sharpness of the HT3050 is really good, first reaction was "extremely sharp!" We expect at least "sharp" from single chip DLP projectors as, unlike 3LCD and LCoS projectors they use a single "chip", don't have 3 separate panels (or chips) to align.
But there are two things of note. There is a little softness by the corners and sides if focused on the center. I recommend adjusting the focus so that the sharpest point is 1/3 out from the center. (That is fairly typical.)
The more significant issue is de-focusing. It seems that the projector's focus will shift rather slightly over about the first 20 minutes while the projector comes up to full temperature. This isn't a rare problem by any means, we've seen some very good, far more expensive projectors suffer from enough de-focusing for it to be noticeable.
Recommendation: Power up, wait 15-20 minutes. The projector might be a touch off each time you power up, but as I said, it's slight, and you probably won't notice.
Bottom line on the HT3050's sharpness is that it's about as good as I expect from a sub-$1000 single chip DLP projector, and that's a good thing. I would consider sharpness to be excellent overall but for the slight defocusing. I noticed the defocusing while running at full power. I did not observe the problem with eco mode, but then, I spent very little time in eco-mode.
HT3050 Audible Noise
The HT3050 is about average in audible noise, despite specs that indicate that it's quieter than most of the competition. Small projectors tend to be noisy - less space to baffle the noise, and larger exhausts relative to size. Mind you many of the DLP projectors that are physically a lot smaller than this one, are even noisier.
On paper, BenQ claims 29 db at full power, 27 db in Eco mode. We don't measure audible noise, but we have plenty of other projectors here for comparison. In Eco power the projector is noisier than the 4K Sony I have here, that claims only slightly lower noise at full power. Compared to the Epson UB here, which claims either 32 or 33 db at full power, the sound is a bit different, but roughly comparable with the BenQ slightly quieter when comparing full power modes. The BenQ has a slightly higher pitched overall sound (probably in part due to the color wheel), so I actually favor the Epson from a noise standpoint (it though has a low rumbling component with its dynamic iris engaged. If I had to guess, relative to what others claim, just from working with it, I'd figure 32 db/ 28 db. Still, quieter than many, and definitely quieter than the ones that are much brighter.
Is this a problem? For the seriously noise adverse, Eco mode likely will do the trick for you, better, but not a whole lot quieter (2-3 db is "slight"). Still, I can't complain about the audible noise levels.
Bottom line - noise is fairly typical for under $1000 projectors, and it is quieter than some. Interestingly BenQ claims the HT3050 is quieter than the HT4050 if I recall correctly. I never had them both running at the same time.
In the images above background mosquito noise is most easily seen in large out of focus areas (such as behind Katniss in the close up with the announcer behind her). Also in skies and other soft surfaces. The other closeup of Katniss seems to be intentionally grainy, so extra image noise further enhances that graininess.
HT3050 Image Noise
Overall, I like the BenQ's handling of image noises. Generally I find the mosquito - the background noise of single chip DLP's to be noticeably higher - that is, easily more noticeable than when viewing on 3LCD or LCoS projectors. Like the HT4050, it seems to be a little less obvious in terms of that background noise than the average DLP projector.
The projector didn't have any issues worth mentioning running my old Silicon Optix test disc.
When it comes to motion artifacts, no noteworthy issues here, either. I don't particularly look for noise issues when viewing 3D, other than cross talk, and as you would expect from a single chip DLP, there's no inherent crosstalk being generated by the projector that I can determine.
At first I was horrified by the amount of light leaking out of the lens focus/zoom and lens shift area at the top of the projector behind the lens. Wow, that put some significant light on the ceiling above the projector! I was really prepared to diss the HT3050 over how much light. That's not surprising to find significant light leakage on some of these projectors. Consider; The very short throw lens versions (the W1080ST, for example), leaked way too much light through the lens and exhaust.
If you could have listened closely at the moment of my epiphany, you probably would have heard the sound of the palm of my hand smacking my forehead, my eyes rolling at my foolishness, and "duh" coming out of my lips. Why?
Because the HT3050 does not leak light out of that lens area, unless you make the same oversight I did! There's a small door that slides forward to close off the lens controls. And once you do that, bingo, not light escaping that way!
Bottom line: No harm, no foul. Light leakage is not a serious issue for the HT3050.