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omar robles
07-27-2011, 07:38 PM
So we shot a scene for my project this weekend. In playing with the footage I see a lot of compression in the footage. The red we shot with is the mx, so I am confused as to why its so noisy in the shadows. The only technical information I can provide is that we set the camera to 320 ISO. Could my dp have set something wrong to have caused this footage? And before you ask we had a lot of lighting, so its not like it was underlit.

Johnny Friday
07-27-2011, 07:43 PM
hard to tell with low rez jpg....a higher rez may help, but what happens when you raise iso to 640, and drop a curve to crush the blacks; raise highlights?

omar robles
07-27-2011, 08:37 PM
We didnt raise the iso past 320.

Johnny Friday
07-27-2011, 08:40 PM
yes, but did you try to raise it in post in Redcine X---you do know you can change ISO as it is only metadata yes?

omar robles
07-27-2011, 08:58 PM
Well if were to raise it in redcine x and i had it set at 320 iso wouldnt it create even more compression artifacts?

Steve Marshall
07-28-2011, 09:01 AM
It really doesn't matter what you had the ISO of the camera set at. It's purely metadata - the ISO setting on the camera only effects the image of your monitor. The sensor will record exactly the same data at any ISO on the range.

Just try what Johnny suggested and I think you'll be pleasantly surprised.

Patrick Tresch
07-28-2011, 09:09 AM
ISO or gain is not compression related. Compression could be seen as blocking or other artefact.
With Mx you can go up to 1000 asa without gain. Do you use Epic? What redcode compression did you use?

Filip Orlandic
07-28-2011, 10:54 AM
I suggest You to trim the R3D raw file and upload a single frame or even better one second. We can take a look and see what is going on.

Dan Kanes
07-28-2011, 11:08 AM
did you shoot 2k?

Johnny Friday
07-28-2011, 11:47 AM
And before you ask we had a lot of lighting, so its not like it was underlit.

I'm not sure how this is lit...but i'd say it's within the MX range....but well lit & enough lite? doesn't look it to me, but very difficult to tell with this low rez pic.

Patrick Tresch
07-28-2011, 12:16 PM
did you shoot 2k?

good point...

In 2k you still should not see any compression artefact but a softer picture.

Can we have a R3D trim please?

Never seen R3D compression artifact, I would love to ;-)

Pat