[quote name='tobyloc' timestamp='1344463525' post='15164']
I really like the test footage and am really happy John has released us some more, much appreciated. I am also looking forward to the camera arriving but I am a little worried now, that noise in the car's shadow does not have a film grain to it, it's got lots of banding in it and looks pretty hideous. Looking at the file in quicktime player it's a bit brighter (qt gamma issue?) and more obvious, this is a screengrab:
It's not in the other shadows so it is unusual, I'm not a techie but could that side of the sensor be overheating? This might be from the honest, sensor data with no noise reduction but noise reduction can't get rid of banding so I'd discount that. It's the kind of noise you might see on a 5D2 if you underexposed at high iso, and then raised in post, which worries me.
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It's not the sensor overheating.
You can usually see this kind of fixed pattern noise when you lift the blacks of the camera beyond normal. Now the camera has a wide dynamic range. You're seeing the point where the dynamic range is bottom out and intend of black you're getting the black calibration of the sensor.
Now this CAN be exacerbated by very hot cameras and hot environments. I've seen it on Canon dSLRs when they've been on and operating contioniously.
IN this case I DONT think this is what's happening.
I think what you're seeing is where the blacks run out because the sensor has run out or DR and you're left with that kind of noise. It's no longer useful shadow information. In the grade I probably should have paid a bit more attention and crushed the blacks by half a percent till it disappeared.
This shot is a very difficult shot. It's backlit and I'm trying to hold (largely succeeding) specular highlights, in an image that also has a lot of shadow. That's a huge ask of any camera.
In a camera that was doing more processing in camera, you'd just have those values down there in the blacker than what the sensor can capture values turn to solid black.
In a camera like this, you need to pay attention and remember to do it...or choose to leave it in for the marginal shadow information that's there in near black.
That's as near as my LAY understanding of how it works.
You get everything, including the marginal stuff normally truncated by other cameras. This is really a grading choice by me to leave more information IN than I probably should from a camera that gives you everything.
Post is CRUCIAL to getting the most from this camera.
jb