10-bit Log to 8-bit workflow

Help
1

I’m not sure if I’m using Kdenlive right with following workflow:

  1. Source footage recorded on an OM System OM-3 in 10bit H.265 in OM-Log400 mode, color primaries: BT.2020
  2. Kdenlive project created with Color space: ITU-R 709
  3. Source clip added to timeline, warning with text “No profile found for your clip… Create and switch to new profile…” cancelled.
  4. Curves effect added to modify highlights and shadows a bit (but Luma formula has only Rec. 709 and 601, no BT2020, so should I use and another effect to achieve this?)
  5. Apply LUT added as a second effect
  6. OMSYSTEM_OM-Log400_BT.2020 to_WDR_BT.709_v1.0.cube file selected in the effect, which was downloded from OM SYSTEM’s site from a page titled 3D-LUT File for Blackmagic Design DaVinci Resolve.
  7. Project rendered.

The result looks ok, but is this the way to do this? Thanks in advance!

2

Hi, and welcome to the forum and community.

The steps are looking good and not too complex or overdone. I would check whether your camera can record in R.709. And 10bit color depth goes out the window as soon as you apply an effect and Kdenlive goes back to 8bit (there is discussion and work about enabling 10bit effects).

3

Hi, thank you for the clarification. Then there is no point in recording in 10-bit if I want to edit it with (current) Kdenlive (with effects). I wanted to preserve as much data (like in RAW photos) to do some highlight/shadow adjustments in post-production, and converting with OM System’s LUT to 8-bit just at the end of the effect stack.

5

Where can I follow this discussion or work? I’ve tried finding an issue.

6

Yes, that’s a very interesting question: Why would you record in 10-bit if Kdenlive immediately converts to 8-bit as soon as you apply an effect?
I switched to MP4, full-frame, 25p 420/10bit Long GOP, AAC 72Mbps, HEVC, h645, even though I know that nothing of the 10-bit will remain after rendering. Perhaps I can take advantage of this 10-bit benefit in the future when Kdenlive fully supports it.

I think I’ll stick with 10-bit recording because it is only 440 MiB in size for 1 minute, in contrast to the 8-bit recording in h264, which is 701 MiB in size for one minute, i.e. almost twice as large.