Work with user color transforms

You can work with user-defined color transforms instead of, or in addition to, the built-in color space options. Once you have added a user transform, it appears on the appropriate menus.

To add a user transform to the available options, you need a transform that does one of the following:

• For an input space, your transform must convert from the color space that you want to add into one of the recognized input color spaces (see List of input color spaces).
• For a view or output transform, your transform must convert from one of the available options to the color space you want to add.

Your transform can be a native .ctf file, or in any of a variety of third-party formats. See Supported Color Transform File Formats.

User transforms are stored as .ctf files in the User Transform/LUT Directory Path set in your Color Management preferences . They consist of a reference to the file that contains your transform, which may be stored in any location. In addition, user transforms include additional metadata, such as the input or output color spaces. The metadata allows Autodesk Color Management to automatically construct a chain of transforms to convert from one color space to another via connection spaces.

You cannot work with user transforms if you are using an OCIO configuration file for color management. When using an OCIO configuration file, only the color transforms specified in the configuration file are available.

Color spaces are matched by name. If you open a scene that uses unavailable user transforms, a message appears. Any missing input color spaces used by File textures and other nodes are highlighted in red in the Attribute Editor. In addition, any missing color spaces in image input nodes are highlighted in red in the Attribute Editor and no transformation is applied. See Fix missing color transforms.

Add a user transform

1. In your Color Management preferences , expand one of the transform or color space drop-down menus and select + Add New .

   You can also use the Output Transform menu in the Color Management group of the Common tab of the Render Settings window.

2. In Transform File, enter the path and file name of a LUT or other color transform file.
   Tip: The Autodesk transform collection is located in the synColor/transforms/ directory of the Maya installation location. It includes many transforms that are not available on menus by default.
3. In Transform Name, enter the custom transform's label as you want it to appear on menus.
4. Do one of the following:
   • For input space transforms, set Destination Color Space to the transform's intended output color space.
   • For view and output transforms, set Source Color Space to the transform's intended input color space. If the transform's input is the same as the rendering space, you can select Raw.
5. Click OK.

Remove a user transform

Removing a user transform removes the .ctf file with the reference to a transform from the User Transform/LUT Directory Path, but does not remove the referenced transform itself.

1. Select a user transform in one of the menus.
2. Click the gear icon and select Remove.

You cannot remove any of the built-in transforms.