At present, a front-projection system is the only display that can produce high-definition images larger than 73" (diagonal). Traditionally, there have been three essential requirements for topquality front projection: first, a screen that will provide a crisp, uniform, color-accurate, high-contrast image from corner to corner; second, a high-quality projector optimized for video as opposed to computer presentation; and third, a very dark viewing environment.
Screen makers have long been able to meet the first criterion, although consumer choices were somewhat limited. Buyers could choose screens with various gain values (which determine how much light is reflected in what directions), in white or silver, with or without perforations. (Perforations allow a center speaker to be placed directly behind the screen, but perforated screens are not recommended for use with digital projectors because the tiny holes can create interference patterns with the projectors’ pixel structures.) With the arrival of HD DLP projectors earlier in this decade came the first major screen development in years—the “gray” screen. This new color compensated for the poor black levels of early microdisplay projectors, but it did not change the need for a very dark screening room. Turn up the lights, even a little bit, and say goodbye to black blacks.
Why? Black is created on the screen (regardless of screen color) by the absence of light. In fact, to make blacks appear truly black, some enthusiasts watch films only in windowless rooms (or ones equipped with black-out shades) with the lights out. When ambient light hits the screen, the darkest portions of the content will only appear to be as black as the room illumination allows, and with reduced contrast between blacks and whites, lifelike imagery is lost. Even a moderate amount of light destroys image quality.
Or at least that was the case until now. Enter Sony’s new $1999 80" HCS-W80 ChromaVue screen. Its promise: to allow front-projection systems to produce high-contrast images, even when room lights are turned up.
The ChromaVue is a fixed (doesn’t roll up), 16:9 screen with a narrow, flat-finished dark-gray bezel. The corners have removable clips that hide mounting holes. Weighing just 17 lbs., the ChromaVue may be light enough to allow the use of screw-in anchors or molly bolts to secure it to drywall surfaces (consult your authorized dealer/installer for recommendations). Like most front-projection screens, this one is optimized for use with a ceiling-mounted projector, where light will be reflected downward toward the viewer. (Using this type of screen for table-mounted projectors placed below the screen’s center will reduce image brightness and contrast.)
The video industry often refers to the ChromaVue as a “black screen,” but its surface is really a charcoal gray with a rated gain of 1.7. The secret sauce can be found within its dark-gray plastic surface coating, which, according to Sony, is designed to pass only the red, green, and blue primaries from a UHP lamp (the type found in most microdisplay front projectors, including Sony’s popular VPL-HS51 Cineza).
As I began testing the ChromaVue, it became apparent that it is a specialized product; for best results, users must play by its rules, and rule No. 1 is not to even think of trying to use the screen with an old-school CRT projector. Out of curiosity, I tried the ChromaVue with my multiscan (analog) Zenith 1200 8" CRT projector, but because the projector’s light source is phosphor-based and not UHP lamp-driven (as the screen requires), the resulting image was, not surprisingly, really dark. As Sony says, CRT projection is incompatible with this new screen technology.
I moved on to an Epson Cinema 500 LCD front projector, with a rated output of 1000 lumens. The resulting image was far brighter than that produced by the CRT projector, but it was still way too dim in the darker areas of the picture. I surmised that the cause was a combination of light output that was too low and a gamma curve that was incompatible with the ChromaVue (gamma is the rate of transition from black to white). Rule No. 2: Use a UHP lamp-driven projector with adequate light output and gamma compatible with the ChromaVue screen.
The ChromaVue seemed to be the lowest-output 1.7- gain screen I’d seen. I generally use a Stewart screen with rated gain of 1.3, and I’ve also recently used the Grayhawk RS; both produced excellent (bright) results with the Epson projector. Why, then, did I get such dim images with the ChromaVue? I called Sony, and was told that the ChromaVue is optimized for the characteristics of the company’s VPL-HS51 LCD front projector and that I should therefore use an HS51 to evaluate the screen. I was curious about this, since the HS51’s output is rated at 1200 lumens, just 20% higher than the Epson projector. A sample HS51 soon arrived, and when I fired it up, I was immediately struck by the fine image quality of this moderately priced projector (and its quiet operation and front venting, which kept me cool wherever I sat). Rule No. 3: For sure-fire results, use the ChromaVue with Sony’s own VPL-HS51 projector ($3500, reviewed in Issue 61).