Light output. The H5370BD is rated at 2500 ANSI lumens, and the maximum recorded from our test sample was a respectable 2127 lumens in the projector's brightest mode, Bright. Bright mode has a noticeable color bias towards green, so it's most useful when ambient light is a serious problem and you just want to make sure people can see the image.
Standard mode, which is the projector's default, produced 1569 lumens on our test unit. Standard mode's contrast and color are much improved compared to Bright mode, but light output is decreased by 27% as a result. Standard mode is the go-to for living room and home entertainment use, as its high output will still help combat ambient light without the ugly green color cast of Bright mode.
Movie mode, at 1358 lumens, is not terribly dissimilar from Standard mode until you disengage BrilliantColor. Turning off BrilliantColor improves image balance by reducing the brightness of highlights. It also makes colors appear more fully saturated and improves gamma (since 100% white is no longer being made unnaturally bright). This reduces light output to 675 lumens, however, so it is best used in a light-controlled room.
In any preset image mode, light output can be further reduced by switching to Eco lamp, which drops output by 17% and increases lamp life by 1,000 hours. For more fine-tuned control in modes where BrilliantColor is enabled, you can also adjust the projector's White Peaking control to raise or lower the brightness of highlights.
Contrast. The H5370BD displays some mild compression of the image's dynamic range. Shadows are sometimes crushed in the very low end but this is somewhat typical in home entertainment projectors, where ambient light more often than not wipes out shadow detail in a significant portion of the image. Black level is comparable to other home video projectors released this year; it is good enough that the H5370BD can multi-purpose as a home theater projector, but not nearly as good as dedicated home theater projectors that are much more expensive.
Color. The H5370BD has excellent color for a home entertainment projector. Standard mode as preset at the factory produces a smooth, consistent 7000K grayscale with no major flaws, even in the shadows. This makes Standard a good choice for living room use, especially since ambient light tends to be yellowish (especially when it comes from incandescent bulbs or compact fluorescents meant to mimic such).
Movie mode is both less consistent and less accurate than Standard mode; it measures about 7200K and has more variation than Standard's smooth, even grayscale.
Switching off BrilliantColor starts to ameliorate the situation by increasing red and decreasing green. The net result is an average color temperature closer to 6900K with less variation. If you don't want to get into the nitty-gritty of adjusting the projector's grayscale more fully, this is the best color available without any real calibration.
With some small adjustments, though, the H5370BD's grayscale goes from "okay" to "great." By reducing blue and green and bumping red, our test unit produced a near-perfect 6580K average grayscale.
The Bias adjustments are more important than the Gain adjustments, as the Bias control is far more sensitive. In fact, leaving the Gain controls at their default 50 only alters color temperature by about 100 degrees Kelvin despite the huge adjustments made in our final calibration.
As for gamut, the H5370BD does include a color management system (CMS), but really digging into gamut is much more difficult than adjusting grayscale. Most users of the H5370BD won't bother, but luckily you don't need to. The default gamut is close enough to the Rec. 709 standard that the differences won't be visible unless you do side-by-side testing against a reference monitor.
Sharpness and clarity. A 720p projector like the H5370BD will not have quite the sharpness and clarity of a 1080p projector. All 1080p content fed to the H5370BD must first be compressed to 720p, and some detail is lost as a result. However, the end product is still much higher resolution than standard DVD and looks quite good for the money.
On the upside, the H5370BD has no noticeable inter-pixel gap (the dreaded "screen door effect"). Sitting at 1.25 to 1.5 times the screen width eliminated pixelation, and sitting at 1x the screen width was acceptable for video gaming (where pixels are more acceptable).