2017

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.
1312 | Chapter 25 Colour Management