Have to say this is down to bad videos. I tried promethious trailer on youtube and the blacks arent perfect although none of the effects this thread is suggesting.
Expendables HD looks perfect and the blacks are almost black with none of the problems suggested in this thread.
Dark knight rises trailer is a little greyer on the blacks but no artifacts.
What I have noticed is all the videos with issues are the apple trailers, so i'm blaming apple, as all the none apple trailers I watch have perfect black backgrounds!
This is UK GNex on 4.0.2 stock on orange. Normal lighting, 50% brightness.
Yes, this is "purely" a video quality issue in some respect, because uncompressed or sufficiently high quality videos will not display the artifacts. But it also is a hardware/software issue too, b/c this type of screen is known to show these artifacts, but maybe a software fix exists... I'm not really sure. It's not
only a video quality issue, because the artifacts cannot be seen on different screen types and it purportedly varies from GNex to GNex in severity.
I just watched the iron man 2 sample... didn't watch that one before... and notice a poor banded gradient in the horizon behind iron man, and some artifacts in the smoke early on in the scene. Also, this was on full brightness in a 100% dark closet with MX player (screen set to 100% brightness both in MX and in settings, turning brightness down in MX and the artifacts disappear for the most part). The video in general is very bright, I notice details that are not visible
at all when watching it on my laptop --- however,
even on my laptop, I can see some banding in the horizon, but it is much fainter. So makes me think there is something going on with contrast/gamma too... If everything that was black on my laptop was black on the GNex, I wouldn't have noticed anything at all. And turning brightness on MX down mostly makes the artifacts disappear, but the video is then a bit too dark.
I am starting to think that this can be fixed with software for the most part...
***New finding:
On my laptop, I can make the artifacts appear if I open it in VLC and turn the contrast down just a bit!. See screenshot from VLC on laptop with contrast & brightness ticked down, and gamma & saturation ticked up, just a hair each.