Issues with ICC Profiles
ICC profiles do not directly 'calibrate' a display, but act as a 'conversion' process between the 'image' and its associated colour space, and the actual colour space of the display being used. This 'conversion' process attempts to make the images seen on the associated display 'look' correct, without actually calibrating the display. If the same images are shown on the same display via a different graphics program there is no guarantee the images will look the same.
Graphics cards have the ability to use a 1D LUT for gamma and colour temperature (grey scale) management, which 'should' be understood by any ICC profile. Guaranteeing this is the case is not always as expected.
The main issues with the use of ICC profiles are:
- Does the graphics program support the use of ICC profiles?
(Many film and TV programs do not)
- Which ICC profile will the graphics program use, if different ones are available?
- Is the ICC profile based on a 1D LUT + 3x3 matrix, or 3D LUT?
(1D LUT + matrix will never be as accurate as a 3D LUT)
- Will the ICC profile understand and correctly manage any active VCGT?
- When footage is saved will the correct ICC be burnt-in to 'correct' the footage colour?
(If the same footage is played back on a correctly calibrate broadcast display will it be 'correct'?)
Display calibration for the film and TV industry should really be directly associated with the display, as an internal 3D LUT, or a single 3D LUT at the end of the graphics path, either via a LUT box or held as the final element within the graphics software, so acting immediately before the display. In this way the display is effectively calibrate in isolation, as it should be.
ICC profiles rely on the graphics program being ICC compliant, so link the 'calibration' between the software and the display, with inevitable potential issues.
Additional Technical & Support Info.
Operating System: Windows 7/8/10
PC Requirements: Minimal - 2Gig Ram Laptop, with HDMI
Mac Operation: Runs on Mac using any Windows Emulation
User Guides: SpaceMatch DCM User Guide
SpaceMatch DCM Demo: Downloads