A little “How to” to set up AgX and Filmic IN BLENDER.
For years now Blender comes with a standard sRGB view transform and and a set of Blender Filmic view transforms. Filmic is an OCIOv1 config and works exclusively with LUTs.
OCIOv2 offers a more modern approach and can function without LUTs. There is an OCIOv2 config called AgX, which is by Troy James Sobotka, the same person who created Filmic.
Here are three really cool videos from Riley Brown that I found with some background information about AgX. And if you follow Troy on Twitter you probably saw some even newer test results for an improved version of AgX.
This unreleased version will be based on the primaries of the working colourspace BT.2020. A full red, green or blue primary in this colourspace refers to a single wavelength of visible light, so three laser lights with the wavelength of 630nm for red, 532nm for green and 467nm for blue. So be careful how you set your shaders I guess!
I am interested how this new und not yet finished view transform will work and in the meantime here is a simple way to try out the available version of AgX.
differences between Filmic and Agx
Blender always supported the linear-sRGB/Rec.709 primaries like all the other software packages we used for decades. Filmic and AgX expect the same primaries.
Filmic only supports sRGB displays in the provided OCIOv1-config that comes with Blender. You can download on GitHub a more recent Filmic OCIOv1 config that supports P3 Displays on MacOS, but with some limitations. I never actually tried this config, although I am a Mac user, so this needs to change!
AgX supports next to sRGB displays also Display P3 and BT.1886. I also never tried out and compared any of these display options yet. I used AgX for the first time for the article One scene – many images.
Blender has sadly still not a preference setting where you can set the OCIO config that you want to use. Tools like Nuke, Affinity Photo and Krita makes it easier to test new configs.
pointing to another ocio config
I found the easiest way for me to use Blender with any other OCIO config than the default one, is by setting the OCIO environment variable. In this way you don’t need to mingle in the application folder of Blender and it will work out of the box with any new update of Blender.
I described the “installation” method for ACES 1.2 over OCIOv1 here. And I have an updated article on how to do the same with the latest release candidates of the OCIOv2 config for ACES 1.3 here.
To get Blender started with AgX or the updated Filmic config is basically the same procedure, just a different OCIO config is being used.
- Download the AgX or the latest Blender Filmic (v1.1 from 2018) config.
- Place the config.ocio in your user folder somewhere or on a server location.
- On macOS I use Automator to create an App called “Blender_3.40_AgX” and “Blender_3.40_Filmic”. In these Apps I use a shell script to set the OCIO environment variable and start Blender.
The MACOS “Automator” script
or a Windows PC .bat
PC .bat file:
START “Blender 3.4_AgX” “C:\Program Files\Blender Foundation\Blender\blender.exe”
PC .bat file:
START “Blender 3.4_Filmic” “C:\Program Files\Blender Foundation\Blender\blender.exe”
Filmic vs. aGx
I reused the rendering from the article One Scene – many images. In the direct comparison between Filmic and the AgX Punchy version, the biggest differences can be found in the blue and the red sphere.
Which images looks better now? I guess it is coming down to personal taste. Somehow I prefer the blue sphere from Filmic but the red sphere from AgX.
The three spheres in AgX seems have more volume or dimensionality, especially the blue one. But the blue sphere can’t get that saturated anymore.