Noise on movement?

S

steve phillipps

Veteran
Getting something odd with the 371.
Every time I do a move there is massive noise in the background. The first frame grab here is when the shot is static and the second one 2 frames later as it starts to move.
This doesn't look right to me, any ideas?
Steve
 

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Interesting Steve. It might help if you list your video mode, frame rate, shutter speed, etc..

Regards,
Bill
 
This was 1080/25P on AVC-Intra 100, 1/50th shutter speed.
Looks like a compression issue? But on AVC Intra 100? Never seen this on the Varicam, or the EX3 for that matter.
Steve
 
I *think* that he is talking about the much heavier compression artifacts in the second image as compared to the first. If you click on the images to view them full size, you can a big difference. And one would expect with AVC-Intra 100 that the compression artifacts would be about equal on each of the images.
 
The shot is telephoto, the camera is moving and the shutter is 1/50th. Its motion blur.
 
im not seeing any noise at all, the bokeh of the background is smooth and clean to me.

all i see is some blur in the second image nothing out of ordinary .
 
OK, here's another one, this time cropped in on a "noisy" area.
The first shot is on a static bit, the second is about 3 frames later after I start panning.
Steve
 

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I can see the noise in this set of stills. The noise is in a pretty dark area for one thing and the other thing is who is going to notice/care about that little bit of noise in a moving shot? Certainly with all the compression artifacts introduced by television transmission these days, you wouldn't be able to distinguish this artifact from one introduced by transmission.

It is an interesting find, and I'd be curious if the noise would still be there with some more exposure.
 
Thanks Steve I can see what you mean now.

I suspect that you are right in a previous thread post that they have just put some anti noise software in to make the figures look good for testing.

As we all know in the field is a different game and it seems that the uprated 371 may now have other problems due to this noise suppression.
 
It's obviously not just noise in dark areas in the normal sense, as that would just as obvious in the first image as in the second, it's always the movement that makes it happen.
And that's the problem, when you show a moving image you do see it, the background seems to shift with all this changing noise and it draws the eye - or it could just be my eye as I'm looking for it of course, I admit that.
Steve
 
Sounds similar to the other moving background wobble that someone else highlighted last month.

Do you have DRS switched on?
 
Here are a couple more grabs, there is some weird streaking going on here.
These are while moving the camera, and something is not keeping up. Look at the second shot and you've got multiple images of the plug holes.
These are crops and with levels boosted a bit just to make the problem a bit more visible, but it is very noticeable on the original moving footage and through the viewfinder while shooting.
Steve
 

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Hi Steve, i've looked to my old 371 footage and all the shots that i have made have the same problem. I've tried to change format to see if it was only a 25p problem but i've noticed that in every codec or format the problem was still there. It's different from the 1080 25pn sliding-ghosting in low light of the 301. If you increase the gain on 301 the effect goes away ( well you have a bit of noise! ). That's another strange thing of the 371...
Roberto
 
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