LED/Laser Home Theater Projector
November 30, 2012
Light output. One of the biggest obstacles to the use of LEDs in projectors has been brightness. That is in part why many manufacturers, including Viewsonic, are now looking at hybrid systems using both LEDs and lasers in order to make up the LED brightness limitations.
LED/laser based projectors measure their maximum possible light output immediately after startup, so that is how our readings were taken. After the projector has run for ten to fifteen minutes, light output decreases by roughly five percent. The post-warmup numbers are listed in parentheses after the initial numbers.
The Pro9000 is rated at 1600 lumens. Its brightest mode, called Bright, measured 1471 (1395) lumens on our test sample. Bright mode has a green cast, but it is suitable for presentations, non-color sensitive computer applications, and the occasional football game in the living room as long as the teams aren't wearing similar jerseys.
Theater mode is the projector's default. Theater mode measures 475 (454) lumens, and color balance is biased towards magenta about as much as Bright mode is slanted towards green.
Our preferred mode for the best color balance was Standard, which sits squarely between Bright and Theater as far as light output is concerned. Our test unit measured 943 (895) lumens in this mode, and color balance was more visually pleasing than either Bright or Theater mode. This is mostly due to Standard mode's cleaner white, while Theater mode's highlights were tinged green. This is a side-effect of the projector's single-axis white balance controls; by canceling out the magenta shift in the rest of the grayscale, whites are pushed too far and take on a green cast.
While there is no lamp-preserving rationale to engage an Eco mode, the Pro9000 includes one anyway. It cuts light output by 33%, bringing Bright mode to 970 (920) lumens, Standard mode to 632 (600) lumens, and Theater mode to 313 (296) lumens. Since Standard will be the preferred operating mode, this results in a light level that hits the sweetspot for many home theater enthusiasts. Eco-mode also reduces fan noise from a rush to a soft whisper.
Contrast. The Pro9000 specifications list a contrast ratio of 100,000:1. However, the projector has some characteristics that limit the impression of dynamic range in the projected image. For one, it can be difficult to get a "clean" white out of the projector due to white balance concerns. We will discuss this further in the Color section, but an obviously tinted white makes contrast appear less dramatic. Second, the projector's black level is higher than that of other home theater projectors that have been released this year. Third, the projector's gamma adjustment is limited, so the slight detail crush in the projector's deepest shadows can be difficult to eliminate. Gamma is controlled by a simple slider. The default setting of 6 tended to crush detail, while a setting of 4 reduced but did not eliminate this behavior. These factors combined make the projector appear lower in contrast than other projectors rated at 100,000:1.
Color. By default, the Pro9000's Theater mode uses the Medium color temperature preset, which over-emphasizes magenta (or, conversely, under-emphasizes green). You can see that in this chart, which shows our test sample's white balance before any calibration.
Pro9000 Theater mode before calibration
The Pro9000 has limited color correction ability. Instead of separate gain and bias sliders for each color, the white balance controls are limited to Red Gain, Green Gain, and Blue Gain. As a result, we were only able to balance color correctly in a portion of the grayscale.
Pro9000 Theater mode after calibration
What does this mean? As mentioned before, whites don't look as clean as they do on competing projectors due to color cast. Shadows likewise take on a color tint in some instances. The middle of the grayscale is more or less in line with the 6500K standard, but we were not able to calibrate the grayscale correctly in Theater mode on our test unit.
Standard mode, while far from perfect, does yield a white balance similar to that of Theater mode, as can be seen in the graph below. 100% white in particular is far better in Standard mode, which helps give the impression of higher contrast and a more natural image compared to Theater mode.
Pro9000 Standard mode after calibration
As for gamut, you can see from the CIE chart below that the Pro9000's red and blue points actually fall outside the Rec. 709 specification. This in part contributes to the Pro9000's seemingly overemphasized color. The projector does have a complete color management system, allowing adjustment of hue, saturation, and gain for primaries and secondaries, but in order to use it you need access to a color meter and specialized software. You can either hire someone to do the job for you, or buy the gear and learn to do it yourself. The latter can be fun if you enjoy tinkering, but if you are the kind of person who wants your projector to "just work" the former is probably easier.
Sharpness and clarity. Most 1080p projectors are pretty sharp just by virtue of being 1080p projectors showing 1080p content. Due to the Pro9000's comparative lack of contrast and crushing of fine shadow detail, it can look a touch softer than its competition at times.
Input lag. One upside of the Pro9000 is that it measured about 17 milliseconds (1 frame) of input lag in all of its different image modes. While the projector has a Game mode, it is no faster than the other operating modes. Competing home theater projectors in the Pro9000's price range generally have greater input lags and are therefore less desirable for fast video gaming.