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Discussion Starter · #1 ·
Wondering if anyone can offer some advice on what to tweak with a black/shadow issue i have.


Now i'm not sure if this is the transfer or the system. I was watching Star Trek Generations, on BluRay. In some scenes, where it was really dark, and you had shadows and whatnot, i noticed the black was turning 'blue". Like a really dark blue. Very 'digital' in it's look too. Can someone explain what this is?


Watching another BluRay (the newest Star Trek) and it seems fine, didn't notice it at all.


I'm using a Sony 1272 CRT, a DVDO VP20 and a Moome HDMI Gamma Input card on the PJ. Transport is a LG BD390.


Thanks!
 

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Ordinarily I would think the grayscale just had normal drift, but the fact that it is there on one movie and not the other is puzzling.

Also, the digital comment makes me wonder: did the blue emphasis look like it had false contouring (layers) or dither? If so, that could indicate a strong blue emphasis above 0%, but somewhere between 0 and 2% the blue is being abruptly cut off (black crush) while green and red are not. If that's what's happening, maybe the gamma on the Moome card and the brightness/black level of the 1272 need to be tweaked again, or maybe there's a colorspace setting issue either in the VP20 or the Blu Ray player. You could test it with a test DVD that has blacker than black pluge patterns. Put the pattern up and see if you can see the pluge and blacker than black patterns. Temporarily raise the brightness on the PJ so you can see the BTB clearly. Now, isolate the colors, either with lens caps or by turning the colors off with the PJ's remote. If you see BTB with red and green but not blue, but the blue background is still lit up, then that's what's causing the digital look.
 

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Coming from a novice: I've had similar problems that I chalked up to the bloody blu-ray transfers. Some are probably just crap. For example, I watched Surrogates last night and that's a pitiful transfer if there ever was one, regardless of the "motif" of the movie which I call "color-semi-Sepia-crap."


I'd suggest trying several different blu-ray movies and if the problem is only exhibited from a small number then I'd dismiss as a crappy transfer or maybe the intent of the craftspeople. That's what I've done as I've given up trying to fix or explain that problem. Also, I've got an iScan Duo that has allowed me to do a pretty good calibration so that I've go very good gamma, grayscale and reasonable color gamut. The majority of sources look great but a few, that I would think would be nice, are utter rubbish.
 

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Discussion Starter · #4 ·
OK done a bit of fiddling. The issue is caused by the Gamma Correction on the DVDO VP20. It's not a problem as such, it's merely highlighting a poor source. If i put something decently encoded on, such as 2012 or Star Trek on bluray, it's perfect. Not on hint of any artifacts. However, if i put on an episode of Star Trek Enterprise on DVD, i get the effect (and something other effects, like the grain of the background is showing a bit).


So it's really just showing up problems with the source encoding...looks like ive gotta be a bit more picky in what i buy now ! It's like going back to a cheap wine after a tasting an elegant one, you just can't do it!


Currently have my Gamma Correction set to 1.6 on the VP20.


Thanks for your help guys.
 
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