and it is being applied to the result of raw image converted to XYZ D60 colorspace when we are converting non-DNG raw file,
From the name, I am assuming that XYZ_acesrgb is a matrix that converts image from XYZ to ACES colorspace, but is there some transform applied to the conversion matrix that I am not aware of?
Hello,
I started investigating this because I noticed developed ACES images seems to be all shifted toward blue,
and here’s some update on what I found.
It seems like we are using a matrix is a XYZ to ACES transform with Bradford Matrix from D65 to D60 applied.
So there are two chromatic adaptation applied when rendering Non-DNG files.
(CAT02 matrix from D50 to D60, and Bradford Matrix from D65 to D60),
and it doesn’t really make sense to have two chromatic adaptation to D60 applied twice.
Since the code is using libraw to convert to XYZ colorspace,
it seems that converted XYZ is in D65, and not D50,
so the first CAT02 adaptation from D50 to D60 is not needed in this case.
When I applied inverse of CAT02 to the developed ACES images,
the result I got was closer to what I expected.
(Since matrix multiplication is not commutative,
I know it’s not a correct result, but the result seems more closer)
I’ve created a pull request that reflects the change that I made while testing.
(https://github.com/ampas/rawtoaces/pull/108)
Hope my comments are enough to figure out the issue is.
Would be nice if someone from ACES take a look at it,
because I’m not really certain as to what is going on inside the code.
@laserpanda yes! Rawtoaces defaults to building an IDT based on spec sens if it’s available but if not it will used metadata from the file or libraw to build an IDT. Your mileage may vary but it’s worth a try.
I’ve created a pull request that reflects the change that I made while testing.
(https://github.com/ampas/rawtoaces/pull/108 )
Hope my comments are enough to figure out the issue is.
Would be nice if someone from ACES take a look at it,
because I’m not really certain as to what is going on inside the code.
Following up on this, I notice the blue tint issue with DNG conversions is still open on Github. I can verify I’ve had what I think is the same issue.
Attached are five raw conversions for a CR2 shot with a 5D Mk II. The last shows the blue cast for DNG conversions.
Rawtoaces mat-method 0 conversion of CR2 using the 5D MkII spectral sensitivities included with the rawtoaces installation. I consider this to be the baseline as I imagine it’s the most accurate.
Canon DPP CR2 to jpeg conversion, then imported to Nuke ACES working space using utility sRGB. Then some slight luminance-only gamma and exposure adjustment to better match example 1.
DCRaw output as ACES gamut linear tiff, flags are dcraw -4 -o 6 -H 3 -w -T
Exposure lifted by +4 stops in Nuke to match the exposure of the rawtoaces spectral sensitivities conversion. I tried both CR2 and CR2 converted to DNG with Adobe’s DNG Converter as inputs for DCRaw. I got the same visual result for both CR2 and DNG, hence only attaching one image. Overall it’s similar, and warm.
I get the same result for both methods. You can see the image is much more blue which backs up the issue first found by kisakata. I’m showing one example here, but I’ve had consistently the same issue with DNGs with other devices.
I’ve visited the pull request page and the last status update on July 17th was “We’ve confirmed that the XYZ_acesrgb matrix is in fact using a D65 to D60 Bradford matrix. Your code changes are being verified by the admin, to be updated to the source master.”
It would be great to see this fix folded into the version I would install via homebrew. Thanks so much.
(Edited to fix wrong image uploaded and correcting a few things)
For all windows users out there, You can install this software using WSL (Windows Subsystem for Linux) inside Windows 10! Just follow the instructions on the github for Ubunut and you’re fine.
I have also created two batch files to help you install this on your windows machine and later convert raw files by draging them into the other batch file.
You can download the batch files here: https://github.com/ampas/rawtoaces/issues/116
Install the ubuntu distro from the windows store
Launch it onces to setup username and password
Run InstallRawToAces.bat and let it run
Drag your raw files to the RawToAces.bat to convert them to ACES exr files.
I’ve want to use rawtoaces for out textures workflow, but can’t figure out where to get camera spectral data for cameras that are not included in default build? I need Canon EOS 5D mk III + IV, and NIKON D850, but have no idea where to get them.
I was thinking about just reusing data from previous models (eg 5D mk II and D700), but I have no way of telling if spectral data are same or not. Any ideas what to do, what would be best approach?
Welcome Jan and thanks for your first post. Quite sure someone will answer you as soon as they get settled in from the holiday!
Steve T
ACESCentral Admin
Help me somebody for install rawtoaces please! I’m just an animator
I stopped on this part: brew install ceres-solver --HEAD
Terminal say to me: **Applying 941ea13475913ef8322584f7401633de9967ccc8.patch** patching file cmake/FindTBB.cmake Hunk #1 FAILED at 429. 1 out of 1 hunk FAILED -- saving rejects to file cmake/FindTBB.cmake.rej READ THIS: https://docs.brew.sh/Troubleshooting
If I try to install: brew install rawtoaces
I get this: Error: rawtoaces has been disabled because it does not build!
@eoldrk@stobenkin were you able to find a solution? I’ve had the same issue and have been unable to build for months, more specifically since updating ceres-solver.
That said @Thomas_Mansencal with docker it works great thanks so much!
I’m eager to use this software but I get the same error as Ilya.
When I try to build from the source I only get to the ‘make’ step, then he doesn’t find the necessary files anymore. I’ve tried Docker, but it also gives me an error I don’t understand…
Can someone explain how I can manually do the last steps in building from the source?
The Docker container should work out-of-the-box assuming you did increase Docker memory. Ceres compilation requires way over the default 2G Docker allows.
thanks for the docker, I managed to get it going as its not running on BigSur anymore natively… and wanted to try with my Nikon Z6 .NEF raw images but I suppose the used version of libraw cant deal with this or something? (both mat-method 1 and 2 give me similar results) .