Recommendation ITU-T F.780.6 describes the requirements for the use of colour and colorimetry for telemedicine systems using ultra-high definition imaging. It also outlines the requirements for the light source and test object colours, the camera and transmission, the viewing conditions and display, as well as the overall characteristics of the telemedicine system. It includes annexes on test colours for medical imaging equipment, measurement methods for colour capturing accuracy of cameras, and measurement method of colour reproducibility of electronic displays.