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Projector brightness specs are commonly cited in terms of ANSI lumens. And while such specs may be useful in making a general determination of how much light output a given model will yield (a model rated for 3,000 lumens should be noticeably brighter than one rated for 1,000 lumens), they’re ultimately not much use for comparative shopping among models in the same price range. For example, the Sony, Epson, and JVC models in our test are rated at 1,700, 2,400, and 1,300 lumens, respectively, but none of the projectors was found wanting when it came to brightness (the higher-rated Epson did prove to be the champ in that respect).
Sound+Vision’s brightness measurements are cited using a different measurement method, footlamberts (ftL). This method takes into account light that emanates from the screen — the light that you actually see. It’s also useful in that the number can be compared with the brightness measurements contained in our TV reviews. While high light output isn’t the end-all when it comes to projectors, there are situations where a brighter projector will come in handy. One example would be when a larger-than-normal screen is used. Another would be an installation in a high-ambient-light environment such as the one described above. Extra light output can also be a boon for 3D, where the glasses used for watching 3D movies cut down on brightness (a phenomenon you’ve undoubtedly experienced if you’ve recently watched a 3D movie).
As with brightness specs, the contrast specs furnished by projector manufacturers are at best unhelpful and at worst misleading. Looking once again at our projector trio test as an example, the JVC proved to be the contrast ratio king, though the other projectors either matched or exceeded it on certain contrast ratio measurements. (At a rated 50,000:1, it also had a substantially lower manufacturer-supplied contrast ratio specification than the Sony or Epson.) The reason for this has to do with the native contrast concept described above, where the projector is evaluated on how well it performs without a dynamic iris modulating the projection lamp’s output. The JVC’s native contrast measured the best of the three, a factor that ultimately had a greater impact on its performance than any of the contrast-enhancing adjustments it provides.
It goes without saying that viewing in a carefully light-controlled room has a beneficial effect on contrast: The less the amount of ambient and direct light hitting the screen from sources other than the projector, the deeper the black level you’ll perceive.