ML RAW Colorspace?

[ariaelf]

Some of my indie film friends are debating about this - so I thought I'd ask. What is the colorspace of ML RAW on a DLSR camera like the 7D? Is it still the original 4:2:0 that you get with H.264 compression, or does it improve?

I have tried searching the forums with keywords and couldn't find an answer. Would a 7D with ML RAW be suitable for green screen work?

[Levas]

it's definitely not 4:2:0.

For as far I know, raw files don't have a colorspace...
Raw delivers you a recorded bayer pattern where each pixel is green, blue or red and there are 16384(14bit) values of brightness for each pixel.
Once debayered it gives you a normal picture, on export(tiff, jpg etc.) comes the colorspace, before there is no one (I guess  )

I don't have any experience with a green screen, but raw has all the color data there could be, there's no step up...so raw should do the job

[chmee]

(a) as raw/mlv-file it has no colorspace - as known from the photography, canon raws can stand ProPhoto as well. so, its enough for all.
(b) because its bayer-pattern, the resolution is green 50%, red 25%, blue 25%.
(c) its not really comparable to yuv-compression-formats. bayer-pattern is needed to be demosaiced, so there is synthetic data, but its clearly better than the yuv-compression of chroma-channels. yuv-compression (or better transmission-standard) was/is not designed for re-synthesizing.
(d) yes, demosaicing brings own caveats/drawbacks - but it lasts for arri, so it should last for the indy-scene

yes, it would be suitable for keying-works (in cropmode!), especially green, because it has the highest native resolution. the 14bit bitdepth gives much more control over the keying-mask.

regards chmee

[dmilligan]

Andy600 has some good color science explanations in this thread:
http://www.magiclantern.fm/forum/index.php?topic=10151.msg138372#msg138372

[reddeercity]

I'm Currently working on a Green Screen Music Video in FCPX (10.1.4) That I Shot  256 GB Of MLV/Raw from 5D2. with 50MM Sigma F1.4 EX DG
In 1:1 Mode @1872x936 23.976 then made 16bit ProRes 4444XQ+alpha files in A.E. with acr. @450Mb/s .mov's
I can tell you that chroma keying is a breezes, I'm amazed at how far I can push thing it truly blows me away sometimes 

[ariaelf]

Thanks for all the replies... though I still don't understand the details, it sounds like doing green screen work with ML RAW on a 7D won't be a problem?

reddeercity, that's awesome Using AE for your keying/FX work presumably? I'd love to know the details of your process!

[reddeercity]

@ariaelf , I guess I could but No all my Keying/FX is being done in Final Cut Pro X .
I use the native keying tools & SliceX plugging for all the Roto Scoping & Tracking.

I just use A.E. & ACR with a Tone Curve to generate ProRes files in Legal Color space.

[ariaelf]

Thanks for the reply reddeercity, I am on a PC so I guess I will have to find other methods