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Discussion Starter · #1 ·
Once in a while, i notice the highlight on an actor's face appears to be grainy. I mean the part of the face that is bright as opposed to the rest of the face skin tone. Usually the nose - where the bright part doesn't blend with the other skin tone, just like oil and water, they don't mix.


I hope you get the idea. Is this chroma bug? Is there any way to correct it? This happens occasionally in movie when you have close ups or when there is great contrast in brightness. Similar things happen in gladiator when there is dark scene and there is torch light, there is artifact in the glow.


I am using a JVC pro scan player with component/VGA in.
 

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Try turning down the contrast. Digital projectors can push whites up so high so that detail in the white sections are lost. Same as losing shadow detail on the black side of the scale. If you have AVIA, use the needle pulse pattern to set contrast by making sure you can see both bars in the white section.


Hope that cures your problem.


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John
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I noticed this same thing on the noses of Brad Pitt and Julia Roberts in The Mexican. I have an LT150, Sony 700P, and a Da Lite Hipower screen. This is a very bright movie at times, and during the close-ups on the faces during these bright scenes, their noses seemed to come alive.


I will try turning the contrast down a bit.
 

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Do these anamolies get worse with movement? e.g. If the face suddenly looks up or turns to either side, does the nose and forehead seem to come alive?


If you can get a copy of Starship Troopers, go directly to chapter four and closely observe the troops' faces as the camera pans across the formation. If you see this problem during this scene, then you are realizing one of the more pronounced limitations of the TI hi-res chip( too many mirrors, too little time).


Turning down the contrast will help some, but won't totally cure the problem.


Cheers,

Peter M
 

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As jszaf pointed out, I also noticed this on the noses of Brad Pitt and Julia Roberts in The Mexican. This was with the LT150 and a Tosh 5109. At the time the image was projected against an off-white wall (matte) and the artifact was visible from 8 ft back. I also examined this scene with the player hooked up to a 34WX50 (widescreen, 34 inch, Panasonic direct view) and it was not apparent (not from 3 ft anyway). I assumed it was a scaling artifact. I will check it out this weekend again but this time with WinDVD. Any one have any other ideas?


[This message has been edited by j albert morgan (edited 08-24-2001).]
 

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For these movies make sure the white segment is turned off and this should tone down the harshness. The nose coming alive I think is a pixel problem that you are seeing - probably a scaling artifact or a problem with the DVD player. I've noticed this with my RP91, but not my HTPC or 5109.


Cheers,


Grant
 

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Try the lowered contrast settings and see if it helps.


Another possible example is one of the beginning scenes in The Fifth Element where the priest is handing the poisoned water to the archeologist. With my contrast set too high the sweat on his face appear as scaling artifacts, bright white. With contrast set properly it looks like sweat.


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John
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Discussion Starter · #8 ·
Lowering the constrast certainly helps somewhat. But I don't want to use the same lowered constrast throughout the entire movie. I dont have AVIA. I guess I just have to try different contrast setting to get a happy medium. I doubt whether a HTPC (which I dont have, am using JVC D721BK proscan player and home-made VGA/component break out cable for input) with better scaling can eliminate that.


I am hesitant to go HTPC path, as I read so much problem with Motherboard/CPU compatibility problem with audio cards and audio/video stuttle on the forum.... Any thought/advice from HTPC user on solving the scaling artifact problem?
 

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Sorry to tell you this but a different player, htpc or scaler is not going to fix it if your projector pushing whites to a higher level. It's the projector doing it and only by setting contrast at the right level (either at the scaler or the projector) will it go away. I would recommend getting a copy of AVIA to set brightness, contrast, and color. That way you will not have to guess whether you are getting the maximum out of your pj. As far as proper contrast, it's like ISF calibration, once you get use to it you won't want to go back.


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