How to use Adobe’s extra DSLR color info in Avid MC5/FCP

Cameras
Posted by Admin on 08, May 2011 with 7 Comments
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We’ve all heard Shane Hurlbut say how much better 5D color appears when edited in Adobe Premiere CS5. That’s great, but what does that mean for those of us who prefer editing in Avid Media Composer or Final Cut? For the past several months I’ve been having my DIT transcode media on set to Avid’s intermediate file type DNxHD 175x using Adobe Media Encoder CS5. Before I get too far I need to point out that DSLR media must be edited in a 10 bit format. A lot of intermediate file types (including ProRes and DNxHD) limit color level info to those between 16 and 235. That’s 220 possible color levels out of 256 max in 8 bit codecs. However our Canon DSLRs are recording in the full 0-255 8 bit color space. So say you decide to edit your footage in an 8 bit codec since it was shot in an 8 bit codec. No good. You’ve just limited the dynamic range to 220 levels meaning your DSLR footage is just that much harder to grade. Edit using your NLE’s favorite 10 bit codec so that the 256 possible color levels in your DSLR media will be expanded to fill the greater range of the intermediate codec.

It wasn’t until I got ahold of Technicolor’s Cinestyle that I started trying to see the difference between Adobe and Avid encoded media. Take a look at the clip below. What you see here is some media recorded between takes on a music video shoot with a Canon 7D using Technicolor’s CineStyle mounted to a Kessler crane with a VariZoom. One copy of the clip was transcoded to DNxHD 175x using Adobe Media Encoder CS5 and the other was brought in via AMA and then transcoded to 1:1MXF prior to export. Since Media Composer has no LUT support I had to manually recreate the S-curve file provided by Technicolor. I copied the Master Curves over to both the Adobe encoded file and the Avid encoded file. No further color correction was done. As you can see the Adobe encoded file has some extra latitude where as the shadow detail in the Avid file seems crushed. Take a look at the detail in the jeans and how the transition from Porsche to shadow is non-existent in the 1:1MXF. This happens regardless if I choose to online my footage at DNxHD175x or the 1:1 max resolution options. All media was encoded in the rec709 color space and exported in RGB.

Essentially what this means is that in order to achieve the maximum latitude possible with your DSLR you must shoot with the Technicolor Cinestyle, and then create your intermediate files (whether that be for Avid or FCP, doesn’t matter) with Adobe Media Encoder CS5. Then once you’ve got picture lock you can apply the LUT that Technicolor provides. In FCP you can use LUT Buddy by Red Giant Software. If you’re an Avid DS user you can load LUT files directly. For us MC5 users the best way to apply the LUT is to recreate the S-curve manually via the Master Curves pane under color correction mode. Let me know if you found this tip useful!

-Alex Walker

Director of Photography based in Austin, Texas. Obsessed with image quality.

www.alexwalkerstudios.com @awalker47

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Jared Abrams is a cinematographer based in Hollywood, California. After many years as a professional camera assistant he switched over to still photography. About two years ago a new Canon camera changed the way the world sees both motion and still photography. He just happened to be in the right place at the right time.
  • raoulkarlos

    well this i good news now. but what is the best thing to do if I shot a whole feature shooting with marvels picture style and cutting in avid. ive been editing footage that i brought in with ama (no perian installed) then transcoded with 10bit dnxhd175x. thanks

  • http://www.facebook.com/alexander.i.walker Alex Walker

    I’ve been following this process since January; before the cinestyle came out. You still see a latitude boost no matter what flat picture style you use. Perhaps retranscode your media with Adobe Media encoder and relink your media?

  • tedinfocus

    And what wbout encoding native H264 from camera via MPEG streamclip to Apple prores 422 ?How it compares to Adobe media encoder?
    cheers

  • Paullws

    Great post, thank you. Any idea if the next FCP will improve this?

  • http://twitter.com/unitedphoto UnitedByPhotography

    Great video to post and hightlight the Adobe VS Avid LUT, S curve and colour rendition.

  • http://www.blendervse.wordpress.com yellow

    I hope you don’t mind my comments but,

    To clarify, 8bit Canon DSLR video like many other consumer video cameras capture luma in the 0 – 255 range, generally 16 – 255 but chroma is always within 16 – 240. It’s very difficult to get a camera to saturate color and go outside of 16 – 240. If luma and chroma we’re full 8bit range or more accurately 1 – 254, then that would not be rec709 but xvYCC or as Sony calls it xvcolor. 1.8x more color information and a wider gamut than sRGB but maintaining the same color primaries.

    rec709 can be full luma range legally, it’s only ‘illegal’ for broadcast, not editing and grading before squeezing into legal range before encoding to delivery codec.

    The whole ‘illega’ description is daft. If a camera captures luma 0 – 255 then that is what it does and is the way it should be handled. If a NLE or transcode tool handles it as 16 – 235 then it will introduce quantization errors, visible as spikes and gaps in a hstogram and artifacts. This is what CS5 is doing along with better interpolation in the conversion to RGB. Like 5DToRGB.

    Users of applications like Avisynth have been happily processing full range video in 8bit form for many years. No need to convert it to 10bit. That is a work around for NLE’s bad handling of it, no real need to convert to 10bit it’s still 8bit’s worth of levels in a 10bit file unless some dithering goes on to generate additional data.

    Whether setting your camera to AdobeRGB or sRGB for video doesn’t matter. rec709 video is always sRGB color primaries, rec709 transfer curve and encoding flagged as such. That includes using Cinestyle, it’s still rec709.

    rec709 has received a bad reputation for steep contrast & crushed shadows because so many NLE’s have handled it badly when they convert it to RGB for color processing and display. Properly exposed, full range luma, rec709 video is no where near as contrasty as believed.

    Where you mention RGB and rec709 do you mean that you have transcoded with full 0 – 255 levels rather than 16 – 235, 240? and kept it as YCbCr or have you done a color space conversion to RGB?

    It’s confusing, 8bit is 256 levels whether it’s YCbCr or RGB. Again NLE’s at fault with their weird descriptions calling 16 – 235 video levels and 0 – 255 RGB levels.

  • Haukez

    I think it’s possible to get decent results in Avid too directly. But the Settings in Media Composer are quite confusing and will lead often to misinterpretation – a complaint from users and a source for confusion for years. In fact you have to choose setting kind of the opposite you would guess…

    It’s Important to understand that Avid in the Beginnings was build to deliver Broadcast Levels. Everything else would be handled outside of it (DI Workflows for Instance). In a World of Online Delivery and People watching on Computer and Handheld Devices Avid had to move, but it’s still kind of complicated in my opinion. But they’re getting better.

    Since AMA you got two Options of Import Media: still the “Classic Import” (Conversion to DNxHD) and AMA  (or transcode from AMA to DNxHD)
    1.) Here comes the wierd thing:
    In the Classic “Import…” Dialogue Options Window you have to choose “709/601 16-235 Videolevel”. Because this tells Avid “My incoming Video is ALLREADY BROADCAST-SAVE – SO PLEASE DON’T TOUCH IT” (in Fact it’s not but you TELL Avid hereby not to shift Levels!)

    Important (and even more stranger): on Export you also have to select “Video Levels 709 bla ba 16-235″. At Least I was succesful this way. Dont know the Reason but I guess you kind of tell the Encoder what you are feeding him (and not how to tag the file). If you choose “RGB 0-255″ Avid again will shift levels in Order to make the File Broadcast Save.
    Yes, that’s really missleading.

    2. AMA. On Export it’s the same. On Import it’s better: you can choose (rightclick on clip(s) how to handle the Levels, here I choose “do not touch Levels”). It’s recommendet to use AMA these days and transcode from there your Offline Intermediate. When finished, relink to the Originals and Export to higher Bitrates

    HTH, sorry for my Englisch, and Avid should pay me for this
    (no, to be fair: read the Avid Community Forums, there are much more educated and talentented People than me, which is where this Info is coming from. !!! http://community.avid.com/forums/)