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I think RBE are due to a lack of synchronization between the wheel position and the update of the image on the DMD (in fact the memory buffer that memorize the picture frame after frame). The picture displayed in Red is different that the one displayed in Green, different that the one displayed in Blue...


IMO, this buffer should only be updated once the wheel has fully achived R-G-B-(W).


What do you think ?

Could we imagine any trick to put this thing back to synchro ?


Bernard.:rolleyes:
 

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Analog source noise floor issues, combined with source framing/clocking jitter. These are my findings. These effects are translated down the pipe in the DLPDMD imaging engine, and are slightly amplified by the time they get to the eye. Maybe not amplified but exacerbated by the source issues.
 

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Shouldn't an HTPC/VGA source then eliminate the problem? I've heard that a computer source lessens the effect, but it is still there.


I thought I read somewhere that rainbows may have something to do with micro-movements of the viewer's eye. So you'd see the green component of the frame, then your eye shifts ever so slightly, and then picks up the red or blue component in a slightly different position. This seems to account for why some people are drastically more susceptible than others (too much coffee?), and why shaking your head and darting your eyes around can force you to see it.
 

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I may be wrong, but I think vga is still analog.


To get a true digital signal, I think you need to go via DVI input...only you will need to find a projector with DVI in to test this.


DVI to VGA adapter doesn't count either
 

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I noticed serious rainbow issues when I used a cheap 10' cable for component inputs on my NEC LT240 from my Panny RP91. However, with an HTPC at 60Hz and native resolution, the image was watchable. I could still see a lot of rainbows, but it wasn't nearly as bad and much easier to ignore.


I'm pretty sure if I used my short component cable with the RP91 the rainbows should go down a whole lot.


Also, I can see quite a lot of "rainbows" on my CRT RPTV when I switch to some of the lower-quality cable channels. I can only see them if I move my eyes to another object in the scene, and they usually show as a yellow streak.


So yes, your source signal quality matters. :)
 
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