FS7: Compression Artifacts in Gradients

egproductions

egproductions

Veteran
Shooting to native XVAC, cine ei, slog3 cine. Footage generally looks great, however, whenever I shoot with a solid backdrop are anything with a fine gradient, I wind up with compression artifacts and color noise.

Anything I can do about this?

Below is the graded image and here is a dpx of the original:

http://www.eliecreative.com/transfer_2/ungraded.zip

graded.jpg
 
Last edited:
You could always shoot custom unless you believe the hype that its impossible to make look good. Or go Slog but record the LUT. The likelihood that you'll need extreme grading is miniscule.
Thanks for posting - its good to know this is a potential problem. But maybe someone else will have a post fix.
 
is it a paper backdrop? If so the clouds are pretty normal, probably it's what you call artifacts.
The magenta/cyan color shift on the backdrop is a known issue when it comes to over/underexposed areas in a uniform grey.
I don't think this is an issue of the camera or the codec. It also depends on your light source. I don't think it happens in post,
it already happened in lighting but you don't see it on the flat CineEI image. If you look in detail you see the color shift also
in reflections on the table.
It's something I know since ever in film and still photo times.
I usually avoid that scene if I know I cannot correct it in post. my2cts

(download not available)
 
Last edited:
Thank Clermond, I fixed the download link.

It is a paper backdrop, however, I'm not talking about the shadows caused by the paper not sitting perfectly flat but rather the breaking up/artifacts of the backdrop (when viewed at 100%) because are slight variations of shadows. You can even see it a little on her neck/bow. I agree with Razz that I feel like it might is being caused by low bitrate/compression, however, unfortunately there is now way to avoid it other than shooting RAW or perhaps ProRes. Can other people confirm this hypothesis?

Currently I'm shooting at 1000EI, I imagine I would get better results if I shot at 500EI, however, that wouldn't leave me with much headroom for grading.
 
Lenilenapi said:
all details about camera settings and exposure would be great
Click to expand...

4K
Sigma 35mm with Sigma MC-11 adapter
Somewhere around f3.5
180 degree shutter angle
100 EI
Cine-EI, SLOG3 - Cine
Daylight WB
Westcott Skylux for the Key Light, natural Daylight for the kicker. No other light sources.
 
You must log in or register to reply here.
Back
Top