How best to use Phantom Cameras in ACES

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I’m currently on a production using ACES on set (with LiveGrade) through to post which is working out well. However we will have a Phantom 4K on set for a day and I can’t find an IDT for Phantom Log. How would you recommend handling this footage? I know LiveGrade has a Reverse Rec709 IDT but I don’t think you would get the best results using that with the Phantom’s Rec709 output.

Hi Sam,

Just wanted to acknowledge your post. Vision Research isn’t currently an ACES Product Partner, but I’m trying to see if I can find some help for you.

Hopefully more tomorrow.

Steve T

Hi Sam,

Does this project involve a post partner who is supporting the ACES pipeline? If so, they may be able to help support this camera. Recently, SHED worked on “Guardians of the Galaxy 2” and I know that they worked with CODEX to debayer the files and apply a custom out that matched ACES primaries and supported an ACES proxy workflow to keep things in the same space. Final color at Technicolor was done through custom transforms. The camera fell right into place and everyone was happy with the look. I would capture in REC709 and ignore the CDL process on set and leave this up to near-set post partner to color match into the dailies and DI pipeline. I would also follow-up with Vision Research and see what they recommend.

We are also in contact with Vision Research about this topic. We had a few requests for this already, and trying to get such transforms directly from them – or collect the information needed to create IDTs ourselves. I’ll keep you posted when we got news about this.

Hi, I was wondering if you had any follow-up from Vision Research about an IDT in order to work with a Phantom in ACES?

Hello everyone,
I just found this in the Vision Research press release:

“ACES color space support - convert Flex4K cines into ACES color space by converting them to the open .exr file format – new in this version of PCC.”

I hope that is not something you guys know already for a long time, but at least I haven’t heard about it before.
So instead of using an IDT, it could be a workaround to convert the media with the PCC tool from vision research and then import it as ACES2065-1 in the desired software. We are doing some tests right now.

Do you have any experience with the ACES export of the vision research tool? Is it somehow reliable?

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Thanks Sönke, great see Vision Research has this option in there software. My main issue is still the lack of IDT for setting looks on set with LiveGrade. It would be great to see one or the option for the camera to output ACES Proxy like RED does.

It would be great to hear how you got on with your testing Sönke.
I just had a quick look for the article you linked to on Vision Research’s site but it’s now broken and I searched the current PCC user manual for the term ACES and came up with nothing. Just a confirmation that this feature does exist and works would be great.

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Hey there,

A few months ago, I wrote to VisionResearch to see if they could shed some light on their ACES workflow. I’d recommend contacting them directly to see if things have changed, but IIRC, PCC provides a couple different rendering options — “gamma”, “log1”, and “log2” I believe. We were instructed to use “gamma” mode, and manually set the actual gamma value to 1.0. (I think there might be a “tone map” or “lookup table” option as well — that should probably be turned off, but I can’t recall if it actually does anything to the transcode).

Two caveats, though:

  1. Depending on how the footage was shot, there’s a very good chance the sensor clipped values above 1.0. At least, that’s been my experience, pretty consistently.

  2. The transcoded linear values are not mapped to AP0 primaries; they’re “camera-native”… so, effectively undefined as of yet.

If anyone has more / better / updated info, please do share…

Hi Quentin,

Sönke and I work together. It is already a while back we had to use Phantom material.
I still got one clip from a shoot with a colorchecker visible.
I downloaded the new version of PCC 3.44 and converted the .cine file to EXR with different settings and compared this to the conversion to EXR with the PCC version from 2017 that I still have.

The latest version of PCC does the same as the old one when the press release claimed the files are actually EXR 2065-1.

In our tests we came and come to the same conclusion. PCC needs to be set to gamma, not to log1 or log2.
The rest of the settings like the actual gamma setting or gain, if the Tone-Mapping has a Curve or you hit reset - this is all ignored when exporting to EXR.

This is the .cine file, converted to EXR (mode gamma), loaded into Nuke as 2065-1, balanced to the grey patch and overlaid with square patches from the above ACEScg colorchecker.

Hope this helps.

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