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Moire / Interlacing Issues in 4k R3D files

J

Jon Keeyes

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We are trying to deliver a movie right now that was shot on a Red One MX and we have been encountering interlacing / moire issues on multiple shots from various days of production that are not able to pass QC. We have backtracked through everything and have now discovered that the moire exists within the 4k footage out of the camera. We are trying to find two things:

1. How could this have happened?

2. Has anyone encountered this before as everyone involved is at a loss on how to fix the moire issue in the movie.

Thank you,
Jon
 
Can you post an R3D snapshot? Moire in an R3D is pretty rare, usually only happens in situations that would obviously produce it with any camera or even with our human eyes. Or at least it should have shown up in the monitor on set. That is if we're talking about an optical moire in the traditional sense. Perhaps you have something else going on? An R3D snapshot frame or two would be really helpful.
 
It can't be an interlacing issue, since the camera only produces progressive footage. I've seen Red footage be "too sharp", such that it triggers an auto de-interlace in an interlaced display, and fail QC for that reason. A better down-sample filter solved that problem.

Can you post an R3D snapshot (or small trim if the issue is only visible in motion) showing the moire.

Are you sure it was not down to using a lower resolution deBayer?

[Ok Jeff, you obviously type quicker than me!]
 
Stupid question but have u viewed the original r3d's at full rez and are still seeing it? Could it possibly be a missed metadata setting? Shouldn't be any moire. If it's really there for sure, you'll have to use power windows to track and slightly blur it...
 
No RED camera should have moire or aliasing unless the OLPF is removed. Never even heard of it happening. Could you post a sample so we can see. This doesn't sound right at all...
 
There's no mechanism whereby an R3D can become interlaced. Moire is very very rare and in most cases is caused by poor scaling in 3rd party software and is not actually in the R3D itself. Please post up or email me an R3D frame from where you're seeing the moire and I'll take a look for you.

Graeme
 
I agree with Nick's comment on a lower res debayer. I've gotten a few notes back from dailies guys about moire when they asked for quick low res debayers.
 
Jon, you've posted this twice. Please keep to one thread so we can help you better.

Graeme
 
One thing to keep in mind is compression "artifacting" that could materialize if the compression settings were too low (ie 10:1 or 8:1 equivalent, as opposed to say 3:1 on Prometheus). I wonder if that would LOOK like aliasing/moire, etc?

I'm thinking specifically of Prometheus where they chose to shoot 3:1 instead of 5:1 in some of Iceland's less forgiving environments (tundra, sky, ocean) as they were worried the densely packed backgrounds would cause digital compression artifacts if not shot cleanly enough.

Perhaps it's that kind of digital signal breakdown like that, as opposed to aliasing/moire?

best
 
Hi All,
Thanks for the replies. I am working on getting some snapshots to post as well as a R3D sample to share. On set, we were carefully watching for moire and none of us recall having seen it on the video monitor, which is part of what is baffling us. The QC lab is looking directly at the R3D file and seeing the moire. I am going to check on the debayer questions above. As soon as I can get the snapshots and sample, I will make them available. Thanks for the replies so far.
 
As Graeme pointed out, I've posted this thread on two different forums thinking that some people might be watching one but not the other. Sorry about that. I am working on getting some snapshots to post as well as a R3D sample to share. On set, we were carefully watching for moire and none of us recall having seen it on the video monitor, which is part of what is baffling us. The QC lab is looking directly at the R3D file and seeing the moire. I am going to check on the debayer questions above. As soon as I can get the snapshots and sample, I will make them available. Thanks for the replies so far.
 
I'll add into the mix:

Please inform us of which lenses and if any filtration was used.
 
I have detected some false colors on a black and white resolution chart on Dragon footage I shot. Very minor, and what it really means is the Dragon has a perfectly tuned OLPF for normal shooting needs !
 
So glad to see this thread, actually I am editing my r3d's files captured with a Red One MX in Adobe Premiere CS6 and I am also seeing some moire in close up shoots, in the hair and the shirt of the actor, the files are in 4kHD and I`ll downscale them to HD, since I don`t have any previous experience with r3d`s files I am assuming this moire is due to the Adobe CS6 software, and I will appreciate if someone could tell me which is the best way to export the final project from Premiere to a Blue-ray in order to avoid any moire or other strange artifacts, thanks!
 
Scaling is the operation that when improperly performed will induce aliasing. Marcel, if you want me to take a look at the R3D to check that the data is good, just post it up here or get it to me. If you can post a grab of what you're seeing in premiere that will help too.

Graeme
 
Here are the lenses and filters used on the Red One MX for this shoot. I should have some samples to post by tonight. Thanks again!
Alura 18-80 with 80C, and sometimes some Zeiss Superspeeds, sometimes with NDs
 
Our lab has posted an example of the R3D files containing the moire issue for review. It can be retrieved here:
A100_C001_0123EQ_001.R3D
user: wo412274
pass: dKytrh7
Please use either of the following methods to access.
1. login to https://ftp.adshollywood.com right click the file then select download file.
2. Use a FTP program (ex. Filezilla) to connect to: sftp://ftp.adshollywood.com and login with the user/pass above. This will work for either Macs or Window machines
Thanks for the help!
 
Ok, I've got the file in, and I've had a quick look through it. I can't immediately see anything wrong. Can you tell me what frame and where to look, and perhaps a screen grab showing the moire?

Graeme
 
Hey Jon,

You didn't really need to post a whole 2GB R3D. Anyway, I'm downloading....
 
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