Dwin HD-700 video projector JGH Chips In
I wasn't able to try the Dwin HD-700 with a progressive-scan DVD player before I had to pack up the projector and move from Santa Fe to Los Angeles. I sent the Dwin to J. Gordon Holt, who in the past few years has spent more time with 7-inch projectors than I have. He tried the HD-700 with a progressive-scan DVD player in combination with an Extron transcoder, which converts the progressive component output to pure RGB. Take it away, Gordon.—TJN
I borrowed Tom's review sample of the HD-700, but because I use a low projector table (as opposed to Tom's ceiling mount), I had to discard his geometry setup and do it all over again from scratch.In most respects, I was immensely impressed with the HD-700's convergence stability, detail, brightness, contrast, shadow detail, color, and almost total absence of fan noise. The scaler does a superb job. Scan lines were completely absent, which gave the picture an exquisite, creamy, filmlike look. Yet there was no lack of sharpness. The resolution sweep from Video Essentials showed full B&W resolution out to DVD's theoretical limit of 5.5MHz, and the DVD picture was as crisp as any I've had in my home-theater room. But, like nearly all line multipliers, the TranScanner doesn't have enough sharpness range to optimize laserdiscs, which consistently looked excessively soft.
I usually use scan-line defocusing to spot incipient brightness overload, but the HD-700's lack of scan lines made that difficult. So I used the needle-pulse pattern, but soon found that—contrary to my experience with most projectors—even the slightest amount of line bending resulted in occasional yellow discolorations across the bottom third of the screen. (Intense yellow in any bright picture area nearly always means blue is being overloaded.)
I had a very brief look at a progressive-scanned DVD (in conjunction with the Extron CVC-200 transcoder, which converts the player's component output to RGB), but had time to view only some test patterns. Particularly outstanding was the Snell & Wilcox zone-plate pattern, which was noticeably cleaner and more stable than the TranScanner with an interlaced component input: The fine-resolution line screens and moving concentric circles showed virtually no shimmer. Progressive sourcing looks like a real improvement over interlaced. [The progressive player was the Mitsubishi, reviewed in the November 2000 issue. Steven Stone also comments there on viewing the Dwin with this player.—TJN]
I was less impressed with some other things:
1) When the gray scale looked right to my eye, there was excessive saturation in low-level blues; the blue-tinted shadows in A Bug's Life were deeply saturated. I had to turn the blue screen control (a gray-scale calibration adjustment) down to 0 in order to make the picture look right. But by "right" I mean really, really right!
2) I was unable to get the left and right screen edges perfectly straight. Both had very slight complementary S-curves that could not be removed. Still, these were slight enough that, even knowing they were there, I rarely noticed their effects on pictures. [This usually indicates that the projector is too low with respect to the screen's lower edge, and that the image-shift necessary to center the picture is moving the active raster area out of the lenses' sweet spot, causing a slight distortion.—JJG]
3) The red and blue geometry adjustments were inadequate. There's only one horizontal size adjustment, for green; it's supposed to adjust red and blue along with it, but it doesn't quite. When I switched to the convergence menu, there were such discrepancies at the left and right screen edges that I was unable to converge them properly.—JGH