Color Managing Images for Display

When working with images, you need to transform them from your working space so that they appear correctly on your display. This involves defining your monitor transform and then converting from your working space. In addition, your monitor should be calibrated periodically.

Defining the Monitor Transform

The display/ directory contains transforms that you can define as your graphicsMonitor alias (and broadcastMonitor alias, if appropriate) either in your application preferences or in the SynColor configuration file.

As an alternative to the transforms in that directory, you can use an ICC (International Color Consortium) profile as your graphicsMonitor or broadcastMonitor alias. ICC profiles are the standard method of color managing monitors in the computer industry. This is especially true on MacOS and Windows where it is integrated with the operating system, but even on Linux it is typically possible to obtain an ICC profile for a given monitor. Third-party monitor-calibration products also typically generate ICC profiles.

Because ICC profiles are so common, it is not only convenient to use them as your monitor transform, but it also provides an easy way of interoperating with other software that uses ICC color management (such as Adobe products).

Converting from the Working Space

Once you have defined your graphicsMonitor and broadcastMonitor aliases, you can then apply a viewing transform that references the currentMonitor alias. The currentMonitor alias will use either graphicsMonitor or broadcastMonitor, depending on which display is being drawn to.

The following transforms are available:
  • display/broadcast/HD-video_to_current-monitor
  • display/CIE-XYZ_to_current-monitor
  • film/ADX/ADX10_to_current-monitor
  • film/ADX/ADX16_to_current-monitor
  • RRT+ODT/ACES_to_current-monitor
If your images are not in the appropriate working space for one of those transforms, then you can export a custom .ctf file that performs the required conversions:
  • If your images are scene-linear but not in ACES, then you can convert to ACES and then apply ACES_to_current-monitor. For example, if you are working with scene-linear ProPhoto values, use ProPhoto-RIMM_to_CIE-XYZ followed by CIE-XYZ_to_ACES from the primaries/ directory, and then apply ACES_to_current-monitor.
  • If your images are in log space, apply one of the transforms from the film/ directory to convert them to scene-linear before converting them from scene-linear as above.
  • If your images are video-encoded, convert them to CIE XYZ and then use the display/CIE-XYZ_to_current-monitor transform.
  • To view a DCDM, apply DCI_to_CIE-XYZ from the display/DCDM directory, followed by CIE-XYZ_to_current-monitor. Note that you might need to use a different transform such as DCI-D60_to_CIE-XYZ if a different creative white point was used for the DCDM.

Calibrating Your Monitor

To ensure that the displayed images are an accurate representation of the intended colors, your monitor must be calibrated. Calibration must be performed periodically because the monitor's response drifts with use over time.

With respect to calibration, there are two classes of computer monitors:
  • Some high-end monitors have internal calibration circuitry. These monitors can be calibrated to emulate another monitor that uses a different set of primaries. You use the manufacturer's software to adjust these monitors to your desired aim.
  • Other monitors must be calibrated externally using a third-party product to generate an ICC profile that you can use as your monitor transform.
When working in a video color space for video deliverables on a wide-gamut monitor, there are two possibilities for getting an accurate preview of the final output:
  • If your monitor has internal calibration circuitry, you can calibrate to a video aim. For example for HD video, you can calibrate your monitor to the Rec. 709 primaries, D65 white point, and 2.4 gamma. In this case, you do not need to apply any color management for display.
  • Alternatively, you can leave your monitor calibrated to a wide-gamut aim, and use the HD-video_to_current-monitor transform from the display/broadcast/ directory as your viewing transform.

Calibrating Autodesk Systems

For Autodesk Creative Finishing products that ship with an EIZO monitor (for example, CG245, CG246, or CG277), you can use the manufacturer's software for calibration. The monitor transforms in the display/Eizo directory assume that the monitor has been calibrated to the factory defaults: native primaries, D65 white point, and a gamma of 2.2.

However, these are wide-gamut monitors, and it is sometimes desirable to calibrate to a different aim. In such cases, you should apply a color transform that converts from the working space to the monitor's current aim, if that aim is different from the working space.

Older Autodesk Creative Finishing systems have a monitor that relies on a probe using procedures described in the Lustre Color Management User Guide. These monitors may have different default settings.

Parent topic: Common Color Management Scenarios