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Cant export ACES 1.2 OCIO what I see in 32-bit preview

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I have an EXR from blender thats saved in ACES with the official 1.2 ACES package from the github . When I import it into AP, point the configuration file to pathTo/OpenColorIO/aces1.2/config.ocio and in the 32-bit preview window my display settings are set to the following. This gives me the correct image in the viewport which matches my blender render. However, when I go to export the image, the colors are not correct and washed out since I assume this is just a "preview" hence the 32-bit preview tab title and not applying the OCIO display transform to the final image. 

I tried adding a OCIO adjustment layer but couldnt get anything to work. When I did this I changed the display transform under 32 bit preview to ICC. The input colorspace is ACES-ACEScg since thats what it is and was rendered in in blender. In the Destination color space dropdown I tried a variety of options but none of them worked nor matched the OCIO display transform in the 32 bit preview of sRGB/ACES. The only way I could capture what it is supposed to look like is to either upload the "raw" ACES renders from blender or what i did which was to take a screen snip of the desktop with windows Snip & Sketch. 

Please help me. I am interested in being able to save ACES only - please dont direct me to look at things related to blender filmic 





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We have asked for some assistance from our internal expert, but he may not be able to reply today, thanks for your patience

Patrick Connor
Serif Europe Ltd

"There is nothing noble in being superior to your fellow man. True nobility lies in being superior to your previous self."  W. L. Sheldon


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Thank you. I am just having trouble exporting as a PNG or JPG. They don't even look close to the same. If I export as an EXR the export works fine and matches the 32 bit OCIO preview .


In Blender I can render and save in any image format and have result look the same across all formats

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For the JPEG export, it's going to be RGB-8 rather than RGB-32, which is likely to have a noticeable effect of some kind.

-- Walt
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@d3d13 - What are you trying to accomplish specifically within AP?  Toward the end of your original post you mention trying to save your AP work to ACES [ACES cg presumably] but then you mention that you are trying to export to JPEG or PNG.  Are you trying to export a gamma-encoded version of the AP documented to an 8-bit JPEG or PNG in ACES or in sRGB?

See this video -

take deep breath and watch the entire thing before pointing me to the original post about not wanting to use Blender Filmic.  Even though the video is about using  Blender Filmic LUTs, the video spells out exactly how to generate correct output for a gamma-encoded format like JPEG or TIFF.

Here is the TL/DR version:

1) When you open a 32bit file into AP and have an OCIO configuration enabled in AP, you need to select "ICC Display Transform" in the 32bit Preview panel.  This is critical to getting your gamma-encoded, exported JPEG or TIFF to look correct.

2) Once that is sorted out, you can use your OCIO adjustment layers to do whatever it is you are trying to do - remember that you are now manually overriding color management to a certain extent.  For example, transform your linear ACES data into sRGB to do texture work.

3) Make your edits.

4) Use an OCIO adjustment to bring the file from the transformed sRGB state back to linear.

5) Export to a JPEG, or whatever you need to do.

The key to getting the "correct" low bit depth, gamma-encoded output is enabling the ICC Display Profile in the 32bit Preview panel, and keeping track of your OCIO transforms to make sure your data are transformed correctly for output.  The attached screenshot depicts a 32bit EXR opened in AP with the above workflow, and the exported JPEG of the composite 32bit document.  I used a Curves and a Levels adjustment AFTER the OCIO transform from linear ACES to sRGB (gamma-encoded data) and BEFORE the transform from sRGB back to linear ACES to manually tone map the bright, unbounded lighting of the celling lights back into the overall exposure range for the rest of the image.

As Walt noted, there will be some differences between the two files and how they are displayed, because of the differences in bit depth and the preview accuracy (like the shadow tones in the 32bit file displayed on the left side of the screenshot).  But that is minimal compared to the differences when ICC Display Transform is not used throughout the process.


Have fun!





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I was originally trying to import an exr from a blender render that was rendered with ACES color management and then saved as an EXR into AP, make my adjustments to this image, then export it as a jpg or png in order to set it as user background in windows with my colors being constant and consistent in each program. EXR isnt supported in windows personalization as a background image, and even if there was a 3rd party program that would expand the amount of file formats available for background images, i would be curious to know the exact steps in order to get this process to work specifically for the many ACES source/destination color space options

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  • 1 month later...

After some month that I change my workflow from 3ds Max to Blender and hours of research I have found a solution that work for my workflow.

In Blender
I work with  this Color Management settings:
Display Device: ACES
View Transform: sRGB
Look: None
Exposure: this parameter can be change if you use Photographer add-on because that change the exposure like on a real DSLR camera.
Gamma: 1
Sequencer: ACES - ACEScg

In Affinity Photo
Open the exr
Go to 32-bit Preview
Make sure that you have Display transform on ICC Display Transform, Exposure = 0, Gamma = 1
Select top layer
Add Exposure Adjustment in case you have chance Exposure in Blender - Color Managmente settings
Add OCIO Adjustment: Source: ACES - ACEScg; Destination: Output - sRGB
Add OCIO Adjustment: Source: Utility - Curve -sRGB; Destination: ACES - ACES 2065-1


Here my afmacros.

Let me know if that solution helps someone. 

Blender - ACES Adjustments.zip

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  • 1 year later...
  • 6 months later...
On 4/1/2022 at 7:15 AM, tbelgrave said:

Hiya @michelepoletto Thx for posting your solution, the only thing I'm unable to find is the Utility - Curve - sRGB, how did you come that by chance? image.png.61939f039b3cc82f3258ae0ffc4f4036.png


Hi @tbelgrave.

I supposed that you have downloaded a custom config.ocio from some user from internet just as me, since our presets are the same.

To add Utility - Curve - sRGB, copy the following code and paste inside config.ocio, at end of the file. Any plain text editor is enough to open the file:

PLEASE, keep the spaces. One blank line before the whole code and two spaces before the dash.

  - !<ColorSpace>
    name: Utility - Curve - sRGB
    family: Utility
    equalitygroup: Curve - sRGB
    bitdepth: 32f
    description: |
      The Curve - sRGB color space
    isdata: false
    allocation: uniform
    allocationvars: [0, 1]
    to_reference: !<FileTransform> {src: linear_to_sRGB.spi1d, interpolation: linear, direction: inverse}


Edited by I am a robot
tip about open the file
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