Lets clear a few things up.
You don't need an IDT for raw files in Resolve's ACES environment. Resolve will automatically debayer raw files into ACES colorspace when ACES color science is selected. DNG files
should contain enough information to display the color correctly. If the color is wrong it means the embedded color data is incorrect or incomplete for the scene or even the camera itself.
Tip: always, ALWAYS set your camera white balance and exposure correctly for each scene and lighting change and, if you can, include a proper grey or white reference target at the beginning of each shot. It will save you a ton of effort and guessing later. Taking a still before pressing record will also provide a general color reference and tell you if the app producing the DNG files from your MLV has any issues.ACES IDTs (Input Device Transforms) are for intermediate camera colorspaces (Log-C, S-Log, C-Log etc) and ADX film scans only. Inverse ODTs (Output Device Transform) can be used as IDTs for monitor and workspace colorspaces if required.
I'll say again - DNG files, .cr2 files and most, if not all, raw file formats do not require any IDT for ACES. As long as the sensor has been accurately calibrated to map to XYZ it can be transformed to ACES AP0. The more calibration information included in the raw file, the better the color rendering and reproduction of captured light.
Digital Camera Profiles or .dcp (not to be confused with Digital Cinema Package) are a form of IDT but they do not target ACES, they typically produce a final look (Adobe Color, Standard, Portrait etc). Cinelog-C profiles target an intermediate log colorspace which is essentially a type of compression.
Cinelog-C in ProRes/DNxHD/HR etc can be used in Resolve's ACES environment with the Cinelog IDT (DCTL) or with an additional transform targeting a different, natively supported colorspace such as Log-C. You can also export ACES files (float EXR) by transforming Cinelog-C to ACES AP0 in After Effects and exporting to EXR. ACES data (AP0), being linear, should only be stored as float or half float in EXR containers to avoid any clipping.
After Effects does not write ACES EXR tags which may be an issue in some ACES apps but most assume EXR files to be AP0 by default.Multiple transforms between exclusive, incompatible colorspaces are not a good idea. You will always introduce error and likely some clipping, hue rotation or other issues depending on the method used. Using OCIO as you have described is
'creative' but technically incorrect. I'm not saying the look is wrong because that is subjective and your taste.
Incidentally, doing this is adding an unnecessary step:
Adjustment layer 6 - OpenColorIO
Config. ACES 1.03
Input Space: Utility - Rec.709 - Dysplay
Output Space: ACES - ACES - ACEScg
Adjustment layer 5 - OpenColorIO
Config. ACES 1.03
Input Space: ACES - ACES - ACEScg
Output Space: Output - Rec.709
The transform to ACEScg, being an output in the first layer and an input in the second, is a null operation. You can simply go from Rec709 display (in) to Rec709 (out).
ACES in After Effects is limited but can work provided you set it up properly and there are several ways depending on the source material.
Raw ingest and transcoding using a Cinelog-C profiles requires additional steps in setting up a linear After Effects workspace in order to export ACES EXR files. A different workspace setup is required for grading the ACES EXR files although some Adobe color tools will not work as intended.
Resolve is much better for ACES so the choice is to do everything in Resolve (from raw files with or without transcoding) or transcode either intermediate log ProRes (small) or ACES EXR (massive) files from After Effects. You can also work in a pseudo-ACES environment directly in After Effects using the ACES OCIO configuration for colorspace management (relative to the assigned ICC workspace colorspace) but you then get into a minefield and it's very easy to lose track of things without a constant A/B against a dedicated ACES environment like Resolve. This method is similar to how Nuke works with OCIO but with the advantage of Adobe Camera Raw.
A good check to see if your ACES environment is setup and working correctly is to use these materials provided by ARRI:
https://www.arri.com/resource/blob/67438/a87188ffbb425d3f42d013793f767b93/2018-acesreferenceimages-data.zipThey also have some very useful and detailed write-ups with example configurations (Nuke) on ACES workflows:
https://www.arri.com/en/learn-help/learn-help-camera-system/camera-workflow/image-science/acesResolve and Adobe Camera Raw will interpret your DNG files slightly differently because they are built on similar but different architecture. They use different white balancing and highlight recovery methods. The difference in demosaicing quality is debatable. Also, if the camera data in a DNG is incorrect or incomplete a Camera Profile or ACR itself can override it with correct data. Resolve can only use whatever data is embedded in the DNG to reproduce color correctly. This goes for all Resolve environments, not just ACES.
"best practice" now is to use Rec.2020 instead of Rec.709/P3
Best practice is to target whatever colorspace the intended playback device displays and only ever grade for the device colorspace(s) you can physically view i.e. your monitor(s).
Theoretically you should be able to just swap out the ODT and get the same result across multiple devices but that's never the case. You should never blindly assume a project graded under the rec709 ODT will translate when switched to a PQ ODT. In practice it always requires a trim pass on a calibrated HDR reference monitor to adjust levels but going to HDR also opens up other possibilities to display richer color and enhance details not visible in smaller display spaces. This invariably leads to an alternative, enhanced and different grade.
Lastly. Do you really need to use ACES? I like ACES a lot and I can see the appeal for multi-cam, multi format shows, CGI and collaborative,cross platform workflows but IMO it's overkill for most things, especially if you don't fully understand how it works and what it's for.
Show Posts
)
(is this used for everything?). The Adobe DNG SDK has everything needed for raw color all in one place so it escapes me why devs continue to cherrypick non-standard info from the internet. It must be a coding thing!?
.