Color management


Color management is the handling and conversion of colors. From importing resources to displaying colors on screen to finally exporting textures. Color calibration is important to ensure the same look across applications.

In the application color management is handled via the integration of OpenColorIO (OCIO for short) version 2. OCIO is the standard in film and animation to convert and display colors.

To enable color management, simply create a new project or open an existing one and enable the dedicated settings.

Color management is available since version 7.4.0.

Vocabulary

It may be helpful to know a few technical terms related to color management in order to understand better the associated workflow:

KeywordDescription
Color spaceCoordinate system in which colors are defined.
Working spaceThe color space used inside the application to blend texture, paint, etc.
Display transformDisplay transform converts the linear colors from the working space to the color space of the monitor to display colors perceptually (to be seen by the human eyes). Display transforms often include a tonemapping pass to compress colors to fit the limited range of values allowed by a screen.
ConfigurationA OCIO configuration file. It defines what is the working space, a list of color spaces and a list of display transform.
ACESACES stands for Academy Color Encoding System and is the standard in many application to exchange digital image files. Two version of this standard are included inside the application by default.
TonemappingIt is the process of mapping color values from HDR (high dynamic range) to LDR (low dynamic range). This process helps display approximate the display of a wide range of colors.

Project settings

The project settings can be set when creating a new project via the new project window or by using the project configuration window.

If the OCIO environment variable is present and has a valid configuration file it will take over to override and disable the settings in UI.

The available settings are:

SectionSettingDescription
ConfigurationColor management

Define which engine to use to manage colors.

Possible values:

  • Legacy (default): Use the old hardcoded sRGB/Linear gamma.
  • OpenColorIO: Use OCIO integration.
OpenColorIO configuration

Which configuration file to use to drive the color management settings.

Possible values:

  • Substance (default): use Linear gamma as working space.
  • ACES 1.0.3: use ACEScg as working space.
  • ACES 1.2: use ACEScg as working space.
  • Custom: use a custom configuration file.
Configuration filePath to the OCIO configuration file. Disabled if the configuration mode is not set to Custom.



Color settingsWorking color spaceThe color space used by the engine to work inside the application. This the color space from which textures may be converted to (import) or from (export).



Bitmap import color space defaults8 bit imagesColor space to use by default when importing 8bit image files.
16 bit imagesColor space to use by default when importing 16bit image files.
Floating point imagesColor space to use by default when importing HDR/EXR image files.
Auto detect color spaces

Allow to define the color space from resources based on specific settings.

Possible values:

  • Disabled: use the default color setting, ignore the resource configuration.
  • Parse file name (default): use OCIO naming convention to extract the name of the color space used by the resource.
  • Use config files rules: use the OCIO configuration to determine how to assign color spaces. This parameter has priority over the previous image file color space settings.



Substance materialMaterial color space default

Define which color space to use for Substance materials color managed input/output (see below for the list of channels).




Export color spaces


8 bit imagesColor space to use by default when exporting 8bit image files.
16 bit imagesColor space to use by default when exporting 16bit image files.
Floating point imagesColor space to use by default when exporting HDR/EXR image files.

OpenColorIO roles

Roles are not yet supported in version 7.4.0.

List of color managed channels

Inside the application, which channels are color managed or not (data/passthrough) is pre-defined.

ChannelIs color managed
Ambient occlusionNo
Anistotropy angleNo
Anisotropy levelNo
Base colorYes
Blending maskNo
Coat colorYes
Coat normalNo
Coat opacityNo
Coat roughnessNo
Coat specular levelNo
DiffuseYes
DisplacementNo
GlossinessNo
HeightNo
IorNo
MetallicNo
NormalNo
OpacityNo
ReflectionNo
RoughnessNo
ScatteringNo
Scattering colorYes
Sheen colorYes
Sheen opacityNo
Sheen roughnessNo
SpecularYes
Specular edge colorYes
Specular levelNo
TranslucencyNo
TransmissiveYes
UserX (1-15)

Depends on Texture Set settings.
By default user channels are not color managed.

Overriding a resource color space

Inside the layer stack is it possible to override the color space of a specific resource where it is currently used.

To do so, click on the little arrow on the resource button to open the color space menu:

Color picker

When OpenColorIO is enabled in the project settings, the color picker behavior change slightly:

  • Colors are edited within the working space.
  • A few additional control are added to the interface (see just below).
InterfaceDescription

This dropdown defines the display transform used to convert the current color and adjust the gradients.

Shows the value of the currently edited color converted from the working color space to the color space of the display transform.

Viewport settings

Both the 2D and 3D views are color managed and have a dedicated settings available at the top of the viewport to control which display transform to use:

  • Left button: Enable/disable the display transform of the viewport. If disabled the viewport will display colors as raw/passthrough. This button is enabled by default.
  • Right dropdown: Specify which display transform to use to convert the colors to display them on screen. The default value is based on the OCIO configuration. This setting isn't saved with the project since it can be monitor dependent.

In solo mode (viewing channels individually) the color management is automatically disabled when viewing data channels (see the list above).

Export settings

The main export settings are driven by the project configuration (see above).

Inside the export textures window there is a keyword that can be used to append to the filenames the color space used per texture: $colorSpace.