Charting Gamma Curves, Revisiting REC-709a, and Premiere Pro 2022 Color Management

June 17, 2022

Team Mixing Light, and members, discuss Log Gamma curves, revisit Rec-709a, Premiere Pro 2022's color management, and declining job offers.


Series

Office Hours – June 9, 2022

Mixing Light Contributors Peder Morgenthaler, Jason Bowdach, Joey D’Anna, and Cullen Kelly join host Patrick Inhofer in leading a Mixing Light Office hours discussion. Today’s discussion included:

  • Deconstructing the electronic journey of images from capture to display
  • Revisiting Rec-709a and the assumptions behind it
  • The history of the various Log-C formats
  • The Log10 curve
  • Color managed color grading when you don’t know the camera or recording profile
  • Premiere Pro 2022 and how it’s making a mess of color-managed workflows
  • Declining a job if it’s too much of a mess

Table of Contents

(bold is a member question)

  • 00:00 – Text

Member Content

Sorry... the rest of this content is for members only. You'll need to login or Join Now to continue (we hope you do!).

Need more information about our memberships? Click to learn more.

Membership options
Member Login

Are you using our app? For the best experience, please login using the app's launch screen


Comments

Homepage Forums Charting Gamma Curves, Revisiting REC-709a, and Premiere Pro 2022 Color Management


  • Jamie Neale
    Member

    Another great show, looks like the table of contents on this page is from another show.


    • Patrick Inhofer
      Administrator

      Argh! Thanks for letting me know, Jamie about the Table of Contents. I must have forgotten to detach it from the template I use, and then a later episode was also not detached and its changes overrode this Insight. It’s on my list to sort out.

  • I re-watched this discussion today – I can’t thank you enough for the superb answers you gave to my question!

    As is often the case, just properly defining the actual question is half way to the answer. And Cullen’s demonstration of the steps involved from capture to display was perfect. When trying to teach the overall concepts to people unfamiliar with the subject these visual demonstrations are incredibly useful.

    I came across a great resource from Nick Shaw…

    https://antlerpost.com/colour-spaces/

    …really handy details for all the various transforms out there – although this raises questions of its own. The graphs don’t directly relate to the demo you did, different axis.

    Also, where is the Reinhard tone mapping discussed?

    My goal now is to come up with visuals for every step from camera to display, including 18% grey, what a CRT did vs what we have our LCDs do, what our eyes do… What Resolve actually does when it generates a Grey Scale(!) etc.

    Thanks again!


    • Patrick Inhofer
      Administrator

      Jamie – I look forward to that Insight!!! 🙃

  • I know this is a bit of an older one, but man… I’ve already gotten great value out of my Mixing Light membership, and yet I feel like the whole cost was worth it for finding this video alone. Thank you all.

    I have a question hopefully anyone from the group can answer, or at least bring up to date.

    My post unit largely works in what Peder describes as a “baked-in” workflow, as neither our media nor our editors are centralized. Offline is done in Premiere on a Mac, and then usually a single render of the whole timeline is spat out to the colourist.

    The question is, what is currently accepted “best practices” for the format of this video from Premiere, that least affects the inherent colour and tone profile of the original camera footage, while also offering the most image fidelity to the colourist?

    Because we work mostly social media, our OCF can range from something shot on an iPhone up to BRAW.

    Knowing our source type and settings, I’m hoping to come up with an optimized, up-to-date workflow that offers the colourist the best quality image which is completely effective in a colour managed workflow.

    Manny thanks in advance,

    Sunny

  • There are lots of good tips on the ‘baked-in’ workflow here https://mixinglight.com/tutorial-series/davinci-resolves-pre-conformed-workflow/

    For many types of camera files, a flattened ProRes 422HQ might be sufficient, raw formats you want 444. Make sure you know and test how raw is debayered (Film Gen4?) in the NLE before the flat file is made. Make sure you get EDL comments in the EDL and a reference guide with burnt in record and source timecode but also source file name, helps take the guess work out. Be careful with Premiere Pro and how it assumes RGB files should be exported, regarding the data levels, Full vs Legal video.

    • This is all excellent. Thank you so much Jamie! Yeah, amongst some problems I found with degraded quality on export, I was particularly concerned about the levels issue. I’ve read some articles suggesting some codecs- possibly ProRes- won’t tag correctly on export and lead to conflicts. I’ll take a look through that series! Thanks again!

  • Jamie’s got good comments there. Especially that bit about RGB files. Premiere will almost always export RGB files as full, YUV (Y-Cb/Cr of course) as limited. Which, especially with Dnx variants, can be not what is expected. As Dnx 4444 according to Avid can be either.

    Another crucial data point is that you must set the Sequence Settings to Max Bit Depth and the Export Settings to both Max Bit Depth and the bpc option to 16-bpc. Or you may actually get an 8 bit file exported. Thanks to Jarle Leirpoll for sorting out that issue. Which didn’t used to actually be a problem.

    • Apologies I didn’t respond here Neil… I cannot thank you enough. It’s the exact situation I’m up against, and trying to figure out the optimal settings. It felt like they’d really buried some stuff in there. That’s fantastic to know, as I’d checked off the two export settings, but not necessarily set the sequences themselves to the optimal Max Bit Depth. THANK YOU SO MUCH for this.

    • Hope you don’t mind Neil- or anyone- but a bit of a follow-up question. When setting up a ProRes codec in Premiere, selecting “Render at Maximum Depth” in the export settings opens up an “Export Color Space” drop-down menu. The options are Rec.709, 2100 HLG and 2100 PQ. This starts to make my head spin, with the thoughts of the footage being in one inherent color space, encoded in another without proper transform, then having to be decoded somehow… I’m sure I’m overthinking it, but what should I be setting here or accounting for when transforming in on the Resolve side? Just set to Rec.709 and ignore, transforming out of the known camera space?


      • Patrick Inhofer
        Administrator

        Sunny – unless you’re working in HDR or collaborating with others working in an HLG or PQ pipeline, you can safely set it for Rec. 709.

        • Fantastic! Thank you so kindly Patrick! Yeah, we’re just bread-and-butter SDR over here.

Log in to reply.

1,000+ Tutorials to Explore

Get full access to our entire library of over 1,100+ color tutorials for an entire week!


Start Your Test Drive!
Loading...