Colour profile

In the colour management process, a colour profile is a file containing information that accurately defines a colour space, enabling a device to reproduce the intended range of colours.

Industry-standard colour management uses ICC-compliant colour profiles (or similar). ICC profiles can be recognized by their .icc or .icm file extensions.

  • Colour profiles address the fact that it may not be possible to reproduce all the colours that an observer sees in an original scene or on-screen.
  • The primary function of a colour profile is to select a colour space that ensures all the colours within an image can be successfully reproduced. In other words, the range of colours output to a device, such as a printer, are adjusted to fit its colour space and ensure they are in-gamut.
  • Colour profiles can ensure that original colours are managed consistently as an image makes the transition, for example, from a camera through editing to the paper or screen on which it will be displayed.
  • Editing software such as Adobe Photoshop Lightroom Classic can be set to match the make and model of the camera, the file format, and user-defined settings. These camera-matching profiles ensure that in-camera profiles and picture styles are honoured as they are imported into the editing environment.
  • If a camera is set to RAW, then all data recorded about a subject is saved using a colour profile that may be specific to the camera but ignores all other style settings.
  • If a camera is set to JPG, then data recorded about a subject is compressed using a colour profile that aims to find a balance between file size and image quality. In this case, more user-determined settings may be imported into the editing environment.

Remember that:

  • Camera profiles are derived from the physics of a camera’s sensor, from lighting conditions, and from the subjective colour perception of a scene that a photographer wishes to record.
  • Most editing software maps the profile and setting it receives from a camera to an ICC-compatible colour space such as Adobe RGB, Prophoto, or sRGB.
  • Monitor profiles determine how images are displayed to maintain consistency and enable critical decisions to be made in terms of colour choices.
  • Output device profiles map the colours in an edited image to the colour space of an output device, such as a desktop printer.
  • Printer profiles map the colours in a document to the colours that are within the gamut of an output device’s colour space.
  • Printer profiles often take into consideration specific printing conditions, such as the type of paper and ink.
  • Colour management is crucial in maintaining consistent and accurate colours across different devices and media, such as monitors, printers, and screens.
  • The use of colour profiles ensures that colours are reproduced as faithfully as possible, even when transitioning between various devices and colour spaces.
  • In professional workflows, the proper calibration of monitors and printers, along with the use of accurate colour profiles, is essential to achieve precise and predictable colour results.
About Adobe RGB, ProPhoto RGB & sRGB

The most common colour profiles in photography are sRGB, Adobe RGB (1998) and ProPhoto RGB.

sRGB stands for standard red green blue and has the smallest colour space.  It was developed by HP and Microsoft in 1996 for use with monitors, printers, and the World Wide Web. It is the most commonly used colour profile today because of its consistent reproduction of colours across different platforms.

Adobe RGB, developed in 1998, consists of the same red green blue colours as sRGB but has a larger gamut. It was developed to communicate with standard CMYK multi-function and inkjet printers and is commonly used for printing on fine art papers.

ProPhoto RGB has the largest colour space with a gamut that covers a significant part of the perceptual colour space of the human eye.