HDRx Noise/Artifacts

[Michael Millichamp]

Im posting a red trim in a second. When it uploads ill edit this post.

I was in 10:1 and I just assumed that shooting the image in HDRx would be ok... Weird.

[Mike Lary]

The one constant is that it always seems to happen in 3/4 tones, the dark but not black areas of the frame.

I've seen this as well (on 2.05), and not just in backlit situations (also on overcast days in a dense forest). It's not HDRx specific. Brownish 3/4 tones are most problematic, so tree trunks definitely cause trouble. I've seen it in all resolutions when shooting varispeed with the best compression settings available, but most often with 2K. When it pops up, it wreaks havoc consistently within a given environment - so it seems like a compression problem triggered by certain variables. A fix would be amazing. A cap on frame rates that can't provide consistent quality would be a fair compromise.

[Michael Millichamp]

http://wtrns.fr/_Xm5eIMC1UOZ0HO


Link to the r3d Trim

[Nils Ruinet]

Definately looks like a compression issue, nothing to do with HDRx in my opinion. When I shoot very complex (high detail) scenes like this, I try to use lower compression because higher compression like 10:1 has a hard time keepong all the detail. I remember a time (around buid 16 on the Red One) where such a tree made the camera crash...
Maybe exposing for the highlights and not using HDRx but a lower compression like 5:1 instead would have given you a better result... Would be worth trying.

[Nook Kim]

Just FYI, the 2.0.2 (Alpha) seems to be the most stable firmare as far as image quality goes. We call this artifacts "snowstorm", and we've decided not to upgrade the firmware until this is solved.

[TheBied]

Just FYI, the 2.0.2 (Alpha) seems to be the most stable firmare as far as image quality goes. We call this artifacts "snowstorm", and we've decided not to upgrade the firmware until this is solved.

As far as I know, we have not seen any evidence that these artifacts are linked to a particular build. If you do have evidence of this, please share. We are actively investigating encoding improvements for scenes such as the one in this thread. For best results with any high contrast, high detail scene such as this one I recommend using the lowest compression ratio possible.

[Nook Kim]

Hi Matthew,

We've come to that conclusion after our tests and some posts on the forum. We haven't experienced this particular issue on the 2.0.2, but on the 2.0.5 and 2.0.8. We found a post about the same issue on 3.0.0 while we were testing the build so we decided not to upgrade.

The 2.0.2 is pretty stable except for one time when we had a checker board type of lines over the entire frame, which we issued a support ticket about. We were suggested to upgrade to a later build, but we didn't want to risk our customers with the snowstorm artifact since it was more frequent issue.

Good thing you guys are heavily investigating on the issue. I really want to be equiped with the RC3/RG3 as soon as this issue is solved.

[Michael Millichamp]

Is there a possible fix if I send my footage off to Red or something?

I really want to use the shot, but I guess I might not...

[Jared VanLeuven]

I've been seeing the same thing on footage I shot over the weekend, they've asked folks to email in who are experiencing it, to rob at red dot com.

[Michael Millichamp]

I've been seeing the same thing on footage I shot over the weekend, they've asked folks to email in who are experiencing it, to rob at red dot com.

Email sent.

Hopefully it get's fixed.