Creating CDL on set

Hi All,

I have been absorbing as much info as possible on ACES over the past few days as I have a DP who wishes to set up our next project with an ACES workflow.

I am the DIT on set, up to this point I have mostly set up workflows with camera log and 709/look transforms.

The gig isn’t full livegrade but the DP would like the ability to adjust the look at my cart, creating CDLs.

My question is - for these CDLs to be relevant to an ACES workflow further down the line, is the only viable way to achieve this to output ACESproxy via SDI to my cart and then create a CDL here before the application of the ACES show LUT/look.

That is to say - it would not be possible to have the camera output Slog, as and cdl applied to this would not be relevant for an ACES pipeline?

I note that you write “livegrade” without any capitalisation. Does this mean you are referring to the concept of live grading in general, rather than the software of that name?

What software are you proposing to use for creating CDLs?

The ACESproxy approach is really deprecated now, as it was designed for “naive” live grading systems which could only apply ASC CDL to whatever signal came from the camera, and then apply the ACES output transform as a LUT after the CDL. It is also only compatible with ACEScc, not ACEScct.

All modern live grading systems can take input in the camera native log, apply an IDT and then grading operations in either ACEScc or ACEScct, and then apply the appropriate Output Transform. This may all happen as GPU shader operations, or be combined into a LUT which is pushed to a LUT box, and includes all the transforms from camera log to display.

Pomfort LiveGrade and FimLight Prelight are two applications which can do this. But there are others. Resolve also has a “live” mode, although that does not support pushing LUTs, and the resulting latency may not always be acceptable on set.

Thanks for your reply,

You are correct to note my general use of the term ‘livegrade’ - although I guess it should have had a space in there for it to be a little clearer.

I plan to use Assimilate Live Looks as I have a permanent licence for this and I think it will suit this job.

What you say makes a lot of sense, so as a basic overview it’s best to work on the following basis:

Camera set to Slog3/Sgamut3.Cine
Set IDT in Live Looks as the above converting to ACEScct.
cdl adjustments made
ODT/ACES based show look/LUT applied (709)
Output/monitor based on above