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Discussion Starter · #1 ·
First off I’m new to digital projectors and I not sure if this it normally.


A good example of what I consider “tearing†can be see in the move “Conspiracy Theory†when Mel Gibson is looking into Julie Roberts apartment from the street, she is running on a treadmill, as she is moving up and down running it’s just one big blur. I have picture quality issues whenever there is a fast moving object on the screen. I would like to know if this is normal, and is there anything I can do to eliminate or minimize this effect.


The equipment:

Dell PIII 550

128 Mb ram

Radeon VIVO 64mb

WinDvd 2.3
 

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Discussion Starter · #3 ·
Sorry, should have posted more info.


Res is set to [email protected] White segment=off, Gamma=Natural 1. Projecting from ceiling at about 135 inches onto a 1.5 gain 77x55 screen.


I have done some searching on this forum and think what I am seeing can better be describe as "judder"


This is a excellent post http://www.avsforum.com/ubb/Forum10/HTML/002952.html

that may help.
 

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Lebuck22,


I had the same first impression when I bought my LT150. I eventually found a TI whitepaper that, I believe, explains what's going on. Apparently the projector uses signal processing to reduce the number of colors when a high bandwidth, high motion sequence taxes the throughput to the DMD. The image is then dithered to reduce the appearance of color banding due to the reduction of color. In the end, this looks like a momentary loss of detail and a sudden loss of signal to noise.


When I first bought the LT150, I was temporarily projecting on to a very high gain 10x curved screen. This screen was great with my old CRT because it dramatically improved the image brightness, but it really made this artifact visible in the DLP image. With the brightness high I could see the noise during quick pans. The odd thing was that I saw the noise in the non-picture area of letterboxed movies. I had never seen this before, so I was pretty certain that either my projector was defective or that this was a DLP artifact. The problem is reduced greatly if you use a low gain/no gain screen or project from the ceiling using a high gain screen (effectively making it low gain).


BTW, it's possible that you aren't seeing the problem I am describing. If this is the case then tlastrange's suggestion may solve your problem. 60Hz seems to be the sweet spot for reducing rainbows as well.


-Jens


[This message has been edited by KilgoreT (edited 08-27-2001).]
 
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