Compression Artifacts

[Oliver Koeppel]

did you try to blur the blue channel? The waveletcompression from redcode reduce data the most in blue channel.
Blur it first and resharpen it after.
I don´t think it will be possible in redcine. I did it in combustion with good results

[Álex Montoya]

Or denoise the blue channel.

[Brian Broz]

Great tip about blurring the blue channel.
But most of us (camera people especially) will not be too crazy bout adding yet another step just to process footage.
Again, I'm sure these noise issues will improve once RED has time to address them.

[ChrisLyon]

I'm investigating using the camera to shoot plates for backgrounds for a vfx-heavy feature and the ability to stabilise, grade, zoom, sharpen etc is critical.

Well his comments still are true. If you are rendering out a plate to be used in an image comp with smoke and cc and other VFX, that makes his point even more valid. Once you are moving your image in the final comp, this pixels are going to be re-rendered anyway.

My question to you is why you are wanting to make comps to zoom in on with footage rather than, say, a digital camera like a 10 MP Canon Rebel. You get more resolution which is better for comp work anyway, plus you don't have to constantly worry about motion blur in your plate frames. That would be my number one concern.

And if you were using footage as the plate, then, again he is right- the artifacts won't be visible because of the motion.

I understand your concern but I think it's rather mute at this point.

(Unless you don't have a digital camera)

[John Tissavary]

Well his comments still are true. If you are rendering out a plate to be used in an image comp with smoke and cc and other VFX, that makes his point even more valid. Once you are moving your image in the final comp, this pixels are going to be re-rendered anyway.

My question to you is why you are wanting to make comps to zoom in on with footage rather than, say, a digital camera like a 10 MP Canon Rebel. You get more resolution which is better for comp work anyway, plus you don't have to constantly worry about motion blur in your plate frames. That would be my number one concern.

And if you were using footage as the plate, then, again he is right- the artifacts won't be visible because of the motion.

I understand your concern but I think it's rather mute at this point.

(Unless you don't have a digital camera)

I doublt Animal Logic is going to have a problem getting a 10mp still cam, being one of the premiere vfx houses in the world.

I agree, basically, that the blue channel noise is not going to be much of an issue with plates. But it is a concern, and definitely an issue that needs to be solved asap. As they say, shit in, shit out... especially when you start applying moves in post.

What I'm confused about is that some are reporting the blue channel noise as very noticeable, and others aren't . Is this a difference in critical observation or variance between cameras/firmware/lighting/subject matter etc...?

I believe it's a combination of subject matter and exposure more than just exposure. I definitely noticed noise in some of our night shots, but less so in others with nearly the same exposure.

Anyway, I know Red is aware of this and an improvement is at hand, so I can't wait to see it!

cheers,

john t.

[Michael Lindsay]

The shot that 'bgunsberger' presents is basically almost as demanding as it gets for a digital motion camera (with spatial lossy data reduction.. ) The minutia detail and the color balance are tricky. I mention this for perspective not because I don't want it addressed..

I personally (when there is storage that supports this.. redram?) would like to see higher data rate options.

Michael

[jbeale]

I think Michael Lindsay's point is right on- the Red compression excels on a lot of "typical" feature shots where some significant part of the frame is not in sharp focus. But if you've got a long shot full of foliage detail where the entire image is in focus, something has to give, and apparently it's the darker areas.

[Daniell Simmons]

Well his comments still are true. If you are rendering out a plate to be used in an image comp with smoke and cc and other VFX, that makes his point even more valid. Once you are moving your image in the final comp, this pixels are going to be re-rendered anyway.

Quite the opposite. As the image may be graded, stabilised, retimed, etc, starting with good material is even more important, as each of these image-processing operations can degrade image fidelity.

My question to you is why you are wanting to make comps to zoom in on with footage rather than, say, a digital camera like a 10 MP Canon Rebel. You get more resolution which is better for comp work anyway, plus you don't have to constantly worry about motion blur in your plate frames. That would be my number one concern.

The shots we're working on involve mid-air action above and through forests, requiring moving vegetation and lots of parallax motion. Static panoramic capture is not an option.

And if you were using footage as the plate, then, again he is right- the artifacts won't be visible because of the motion.

The artifacts are quite visible at 2k on a DP90 pretty much out of the box

[Gavin Greenwalt]

Ben to put it simply. REDCode is over compressed for any real serious manipulation of the blue channel. I would investigate the RAW port option to shoot uncompressed. Hopefully there'll be a hardware 4k Cineform option early next year which could enable aerial footage without compression. Or else you can join in the chorus (currently of one :) ) asking for 50MBs REDCode RAW.

[Gavin Greenwalt]

Also I'm seeing some compression glitches in that footage I haven't seen before. It looks like a de-mosaic issue.


Are those in the original or a result of online posting?