Proxies with RAW footage

Hi,

I don't have much time to do deeper testing right now but here's my issue, I have R3D files (IPP2 Camera RAW settings). I generate Proxies using DaVinci's "Generate Proxy Media" function. Then, when I switch from the R3D to the Proxies using "Use Proxy Media if Available", there's a big color difference in the viewer.

I will provide screenshots later. Sorry.

I'm using 17.3.1

EDIT: This is in an ACES project.

The proxies are for editing, so...color not so much important yet.

Hi Jim,

Sorry but I'm not sure I get you. Do you mean the proxies in Resolve are strictly made for Editing? Is this explicitly stated somewhere? Or, since when 4K ProRes 4444 proxies are not good enough for color grading? Are you implying I should be using Optimized Media instead? I turn on the "Use Proxy Media if Available" when I need more playback performances.

Thanks for your input.

since when 4K ProRes 4444 proxies are not good enough for color grading?

Since the originals are RAW and any kind of proxy doesn't allow the necessary access to RAW controls.

My thinking, anyway.

ACEs is likely setting the input color space of the R3D footage automatically, but unless you're setting it appropriately for the proxies, which wouldn't be automatic, they won't match.

I don't think that's true, John. Mostly because we can't change the IDT for RAW media. Or more accurately, any change we make to the IDT has no effect with RAW media. They're simply ignored.

Or, are you suggesting Resolve is using that IDT twice, once for the RAW and again for the Proxy?

It would depend how he has it set up in ACEs. The IDT of the raw footage is established automatically. But are the proxies being "read" accurately? The other issue is, full or video levels, and at which are the proxies being generated....

R3D Clip Attributes
Data Levels: Auto

Project Settings - Master Settings
Data levels: Video

Proxy media resolution: Original
Proxy media format: ProRes 4444

Project Settings - Color Management
Color science: ACEScct
ACES version: ACES 1.2
ACES Input Device Transform: No input transform
ACES Output Device Transform: Rec.709

Project Settings - Camera RAW
Color science: IPP2

I don't work with either ACEs or Red footage (how robust is ACEs support for Red in Resolve?), but it looks like you haven't defined the input color space for the proxies, which is being done automatically for the raw files.

Try this: locate a proxy clip in the media pool, right click, ACE input transform, select the appropriate Red color space.
Does the ungraded proxy clip match the ungraded raw version?

It is irrelevant that you are using IPP2 because working in Managed or ACES Resolve takes control over any raw file format and does it's conversion to timeline from the native camera space (with a conversion step to ACES-2065-1 (AP0) / Linear in between as part of how ACES works).

I think that the issue here lies in the fact that it does this from the source gamut but linear gamma, not the camera's log space. When you render this to a proxy file anything that was captured above 1 (linear light/float) gets clipped because you are storing it in an integer format like ProRes or DNxHR 10bit.

You can't control the IDT for proxies separate from the source files I think so you have two options:

1. Create proxies by disabling ACES management and globally set your raw files to Red Wide Gamut / Log3G10 and then create desired proxies.
Instead of linking the proxies replace the actual source media with them and set IDT to that colorspace until you are done with editing and need to go back to full res raw.

2. Create proxies the same way but do link them as proxies to the raw files.
Create a CST node on your timeline or pre-group grade color page, or on an adjustmentlayer in the edit page with these settings.

2.png (112.63 KiB) Viewed 3668 times

This will correct the mismatch between originals and proxies.
I don't fully know why you need the DaVinci tonemapping with ~31.5 adaptation instead of no tonemapping but that worked in my testing.
Disable that node/layer when you switch back from proxies to raw files.

Far from ideal but I don't know another way..

Thanks for your time Shebanjah, your explanation totally make sense. In ACES the proxies are generated in linear. I tried in YRGB Color Managed - DaVinci Wide Gamut and they're generated in log.

Thanks for the workarounds!