R3DCODE Compression vs Other Compressed Formats (XAVC, H264/5, etc)

[Curren Sheldon]

Hey everyone! I'm a self-taught filmmaker who has been shooting on DSLRS, C100s, FS7s, and FS5s for the past few years. This year, I decided to make the jump into the RED ecosystem and am super pumped for the impending arrival of my Epic-W.

Quick question - I've been looking all over the net and here on RedUser about the compressed RAW formats of R3D. Many of the experienced users seem to shoot in 5:1, 7:1, 9:1 while sometimes saying 11:1 or 12:1 is OK.

My question is, coming from compressed codecs like Sony's XAVC-L and XAVC-I, where is a comparable image quality in RED's compressed codecs? I know it's a much more robust, RAW, and more beautiful image than XAVC, but is that only at the lower compression rates (9:1 and below) or are even the higher compression rates (14:1 - 22:1) still a less compressed and more robust image than the compressed Sony or Canon images? Also, I'm assuming everything else (lighting, resolution (4K)) being equal.

I do a lot of nonfiction and interview work, so I want to find that sweet spot of a nicer, cleaner image than what I've used before with manageable data size.

Thanks!

 

[Jacob Ryan]

A fellow reduser here, Gene Sung, also operates an FS7. He might be able to offer an insight on this. I'm curious myself.

 

[Curren Sheldon]

Yea I will probably do some tests against my FS5's internal 10-bit (50mbps HD) and 8-bit (100mbps UHD) once I receive my Epic-W - but even at lower compression rates, I'd assume the RED is more robust. I'm hoping at least from 18:1 and up is stronger, cleaner, and sharper.

A fellow reduser here, Gene Sung, also operates an FS7. He might be able to offer an insight on this. I'm curious myself.

 

[Joel Arvidsson]

What is nice is that you have so many option to set the compression ratio to suit your scenes. In a well lit interview with a subject in focus and blurred background you can get away with higher compression. A wide shot with deep focus of a forest will be better in lower compression. What is your threshold of what looks good, I cant answer. Its both scene dependent and subjective. Because helium is a new sensor we cant rely on dragon knowlege, but on testing. Also there is the downsampling to take into consideration.

I think Björn has some really intresting thoughts in this thread
http://www.reduser.net/forum/showthread.php?150371-Benefits-of-shooting-8K-Epic-W/page2

 

[Jacob Ryan]

I can see that there must be some situations where your Epic-W must be 'dumb down' to match lower specs cameras, sometimes even an a7Sii or a GH4.

 

[Curren Sheldon]

Hey Joel - Lots of good points. I'll have to test it out and see. But, love what Bjorn said and think he confirmed a bit of what I was thinking. Namely, that shooting with the Helium sensor in 7k or 8k can be done at lower compression rates and achieve a superior image than Dragon or other companies codecs at 4K. Excited to try it out!

What is nice is that you have so many option to set the compression ratio to suit your scenes. In a well lit interview with a subject in focus and blurred background you can get away with higher compression. A wide shot with deep focus of a forest will be better in lower compression. What is your threshold of what looks good, I cant answer. Its both scene dependent and subjective. Because helium is a new sensor we cant rely on dragon knowlege, but on testing. Also there is the downsampling to take into consideration.

I think Björn has some really intresting thoughts in this thread
http://www.reduser.net/forum/showthread.php?150371-Benefits-of-shooting-8K-Epic-W/page2

 

[Gavin Greenwalt]

http://www.reduser.net/forum/showthread.php?124071-Compression-Wedges

My opinion is that something ProRes or HVC is very different to REDCode. REDCode doesn't so much get blurry as you increase comrpession (although it does do that as well) as it gets color splotchy. It aggressively compresses hue and saturation before luminance so the result is you get weird large scale shimmers at high compression ratios. I prefer redcode for low compression but all of the DCT codecs for high compression.

Some animated gifs to illustrate how noise gets more "chattery" at higher compression. 25MBs total. Might take a minute to load. (Note there is a good bit of atmospheric distortion in there too.

EDIT: Changed to links. All of them couldn't play back smoothly at the same time.
2:1
6:1
11:1
15:1
22:1

 

[Marc Wielage]

Quick question - I've been looking all over the net and here on RedUser about the compressed RAW formats of R3D. Many of the experienced users seem to shoot in 5:1, 7:1, 9:1 while sometimes saying 11:1 or 12:1 is OK.

Whenever a client asks my advice in terms of post workflow, I tell them "don't shoot at greater than 5:1 compression if you can, and buy lots of drives." To me, this is the best strategy. I also tell them to pick an aspect ratio that will work well for their delivery format; don't shoot 1.90 full-frame if you have to deliver 1.78 HD. I'd much rather they frame for a smaller rectangular area inside a big 4K or 5K frame so we can crop anywhere we need in post. But they also need to shoot a framing chart at least once a day if possible, just to make sure editorial knows what the correct framing will be.