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April 2002|InFocus (www.infocus.com) announced its new home entertainment unit, the 1000-lumen SP110, (now called the SP for screenplay) at COMDEX in November 2001 with a list price of $4999. The InFocus SP110 looks almost identical to the company's LP530, a 2000-lumen class business projector that lists for $6499. Compared to the LP530, the SP110 may appear to be a $1500 better deal, but price isn't everything. The SP110 is spec'd at only 1000 lumens and has essentially SVGA resolution, where the brighter LP530 has XGA resolution. The SP110 is supposed to have better video, but I couldn't find any difference in video signal compatibility, since both units use the same "connectivity module" and both units employ the same Faroudja DCDi (Directional Correctional De-interlacing) video-processing chip. I got the impression that the SP110 should do more, perhaps from InFocus' marketing, which boasts that this home theater projector is "perfect for big-screen viewing occasions." However, I don't buy that claim since the SP110 lacks light power and is based upon a lower-resolution chip that only allows 480-line viewing in a 16:9 aspect ratio image. For now, InFocus has what they have and until they offer a true 720-line, 16:9 version (sometime this fall perhaps), the options are the reasonably priced and more color-rich SP110 or the more expensive LP530, which features more resolution and light power, but less color saturation. projecting from the inside
As I said before, the SP110 looks like the LP530, but there are some internal differences. For one, the SP110 uses a different Digital Micromirror Device (DMD). Instead of the 530's XGA 1024x768 resolution 0.7-inch DMD, the 110 uses a 0.7-inch, SVGA 848x600 pixel-resolution chip—basically the standard SVGA chip used in business projectors. Right, it is an old design in spite of InFocus' heralding it as an "advanced DLP technology" dual-mode system that supports both true 16:9 aspect ratio display and a 4:3 aspect ratio. The dual-mode action comes from coupling one of TI's older ASICs—supposedly the ED1 chip to the SVGA DMD. The ED1 was one of the first "home entertainment" ASIC chips that TI developed to write to the DMD in a 848x480 pixel, 16:9 aspect pattern—leaving all the excess top and bottom pixels off. When you use the SVGA chip in a true SVGA mode, only 800x600 pixels are used, leaving a few pixels off on each side. I found that the SP110 was brighter when used in SVGA mode since that mode uses about 15% more pixels and, therefore, makes for a bigger, more effective mirror. Anyway, I evaluated an InFocus SP110 using both video and computer input signals. Using a computer's analog 15-pin VESA RGB input signal at 800x600 pixel resolution, I was able to measure 896.59 ANSI lumens with the brightest, wide zoom lens settings on the SP110. This was done with "PC" gamma settings and the contrast and brightness optimized for the best image quality. InFocus spec'd the unit at 1000 lumens. I generally allow about 10% spec variance before I complain—which would be 900 lumens. InFocus says that its spec is really good for PCs with digital outputs and that they get about 5% more lumens with a digital signal than with the analog signal output. If that's true (and I couldn't verify it), then they have an honest projector—but only with a digital PC signal, which doesn't quite jibe with the home theater marketing angle. I also measured the on-screen lumens with a video signal making a 16:9 on-screen image and I found a lot less light than claimed—about half, according to my light meter and depending upon gamma settings. The lower light output in video mode results from a variety of factors. First of all, the LP530's 270-watt lamp output has been de-tuned in the SP110 to 220 watts in order to reduce heat and fan noise. The SP110 uses 15% fewer pixels and, therefore, a smaller overall mirror size when the 16:9 aspect ratio is selected. And when a smaller mirror is used, less light gets reflected towards the screen. On top of that smaller mirror, when the SP110 detects a video signal, it automatically switches the "gamma" setting to "film gamma" from "PC gamma." The gamma setting determines how the input signal is mapped to the available output range. Anyway, the film gamma setting in an SP110 drives the video signal way down to much darker levels—and that reduces the overall output brightness by a lot. If you have a really dark room and a good, bright projector, then when you drive most of the signal down to the darker levels (using film gamma), maybe you can get a more "film-like" theater feeling with lots of dark shadows and punchy whites. On the other hand, PC graphics and normal video signals were designed to be shown in brighter rooms so those signals can use more of the projector's available light—and spread it out more evenly. When I forced the SP110 to use the PC gamma setting, the on-screen brightness in 16:9 video mode got a lot closer to that available with 800x600 pixels. Perhaps using film gamma works with the SP110 in a dark room, but personally, even there I preferred the brighter, higher-contrast images obtained with PC gamma settings. color by numbers
When InFocus announced the SP110, it made a big point of saying that it uses an "exclusive 6-segment, 4-speed color wheel" for "natural saturated colors and sharp contrast." Well, in terms of contrast, I measured 231 to 1 with an ANSI checkerboard pattern against an analog SVGA, PC RGB signal with PC gamma. I saw a lot less contrast with a video signal using film gamma due to the lower white levels. InFocus spec's the SP110 as having 600-to-1 contrast ratio, supposedly using sequential on-off screens rather than the ANSI checkerboard. When I took the ratio of an all-on white screen versus an all-off black screen, I found 486.88-to-1 contrast ratio with the same contrast, brightness, and gamma settings as before. I have poked a lot of fun at one-chip DMD projectors in the past for their lack of color saturation. Since they only use one chip, and not three (which would allow for separate red, green, and blue color paths), they have to time-share that one chip to make full-color images. That's where the color wheel comes in: sometimes it's red and sometimes it's green and then it becomes blue when the blue segment has been rotated in the right direction. The DMD has to change its image and show only the red channel data when the red segment is aligned. The four-speed characteristic mentioned in the marketing literature comes from the fact that they operate that color wheel and DMD chip at four times the video update rates. It you have the turn the crank once to make a RGB image, then it seems to follow that running four times faster should smooth over any problems. Same for the six segment stuff: that's just two separate RGB filter segments, which makes it an RGBRGB wheel that only runs half as fast as a three-segment wheel would need to support that 4X update rate. Some of the standard one-chip business projectors ran at 2X and that low speed allowed for lots of color smearing with moving video images as well as for more visible color flash. The SP110 runs at 4X and that's supposed to eliminate both color smearing and flash. I haven't seen the annoying color flash on the latest rear-screen sets, but I see it all the time on one-chip front projectors and, unfortunately, I see just as clearly with both the LP530 and SP110. The color flash looks like red, green, and blue sparkles coming from bright, moving objects. The opening credits in Mars Attacks where the Martians' fleet of flying saucers rotates through deep space are perfect for viewing color flash in a dark room. Fast and flashy as the SP110's color wheel may be, that doesn't make it colorful. The filters in the RGB segments determine the SP110's color saturation. Weaker filters make for less saturated colors, but stronger filters absorb more light. So it's a trade off, more lumens with less color or more saturated colors with fewer lumens. InFocus chose more lumens and less color saturation in its LP530 by incorporating a clear "white" segment alongside weaker red, green, and blue color filters. The white segment boosted lumens and washed out the colors. They tried to crank up color, but not lose too many lumens for their SP110 home entertainment product by essentially eliminating the white segment and readjusting the density of the colored segments. While the SP110 may have more color saturation than "normal"—I measured 14.46 units of color saturation versus 13.66 units in the LP530—it still doesn't have enough. They'll need to get over 15 units to satisfy the SMPTE color standard—and they'll need to have those colors properly balanced as well before I stop complaining. As compared to the SMPTE standards, the SP110 may be close for red, but it misses the mark for green and blue. When you compare the SP110 to a projector with adequate color saturation, you can see that the SP110 has weak-looking greens and blues and that also affects other colors like yellow. Use the SP110 and look at the Warner Brothers Studio logo shown at the beginning of one of its DVDs and you can see what I mean—the bright yellow "WB" doesn't stand out against the blue background the way it should. hot or not?
Will the InFocus SP110 be a hit? I may not like the color saturation, but the SP110 and its Faroudja DCDi video processing chips did an exceptionally clean and clear job on DVD-Video using the three-RCA jack component video input. The SP110's video and graphics images both had great, almost 500-to-1 contrast ratio, but with less color and brightness than I like. I don't know how well SP110s have sold, but the dealers are reportedly happy to get a new product, particularly one that automatically comes on in 16:9 mode when a video source is attached. Home users are supposedly less likely to want to grab the remote and try to punch through the slowly responding on-screen menu to change aspect ratios from 4:3 to 16:9 when they pop a DVD into the video machine, which the SP110 makes unnecessary. So the SP110 has that going for it—but I'd sure like to get more light output, a true 720p resolution, more contrast, a more flexible gamma and color adjustment along with more color saturation. But I'm picky. The bottom line—I'd be willing to wait for the next generation if I wanted to try to fight with my home decorator for a "big ticket" front-projection system to install in the living room.
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