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I read the X1 review recently mentioned here and saw a description of dithering artifacts, my one complaint w/ the X1:


for me, these artifacts are manifested as individual pixels changing color/brightness even w/o the larger object they're a part of moving or changing brightness & color.


I dislike Bogart's black & white face shimmering in blacks and whites at me (he's probably not happy about it either).

reducing the sharpness setting on the X1 helps.


I watched To Catch A Thief last night (pana XP30, Svideo) and saw a vivid blue sky shimmering at me -- even though the sky wasn't moving or changing color.


[ I'm also wondering if this is a DVD compression artifact ?]


That X1 review mentioned this as an artifact of scaling and dithering and was eliminated with a HTPC. While not wanting to open the HTPC debate here, has anyone tried either an outboard scaler or HTPC and seen a reduction in the artifacts ?


I'm going to PM Bob Williams and ask him these questions -- I suspect the hardware in the X1 is more than adequate to do HTPC -caliber scaling ... I suspect a key algorithm change will be needed though.


thoughts?


Mark
 

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Try using the Component Video to VGA and running progressive scan.


S-video connections are not progressive.


The X1 only accepts a 480p progressive scan signal through it's VGA input.


The Panny DVD might do a better job or assembling into progressive frames, and reduce the artifacts you are experiencing.


I'd try it
 

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I am using an RP-82 480p via the VGA port and if I press my face up against the screen I can see some dithering. I only notice dithering from time to time in bright blue sky scenes but I have to be looking for it. I assume it's a DLP thing and I'll gladly put up with it for the better black levels.


Randy
 

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The source plays a big part here. The dirty little secret about DVDs is they run the gamut from VHS resolution, (DVDs that are simply transfers of VHS tape) all the way up to Superbit DVDs. In my experience the X1 will be artifact free as long as the source is artifact free.
 

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I'll third the comment about the quality of the source material being important in order to fairly judge if you have a signal quality problem. I use an HTPC and I've seen DVDs that "dither" like crazy and others where the large colour areas are rock solid and steady.
 

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So called "Mosquito noise" in skies is a very common artifact of MPEG compression so I suspect the source is the issue with To Catch a Thief. One way to tell if the compression is the cause is to pause the DVD player and see if it stops. If it does not stop, then it could be noise in the analog processing of the DVD player or the projector, and in general this processing is done better by a HTPC (hence the comments that HTPCs reduce "dithering"). Thirdly, it could also be the projector dithering to produce an even gray scale. Even when a HTPC is connected, the projector still needs to dither a bit spatially to prevent contouring of the image. This occurs mainly in dark areas of the image.
 
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