The Lab color space is often the preferred choice when color calibrating, particularly when measuring and matching colors from reference targets. The Lab color space consists of a Lightness coordinate (0 equals black and 100 equals white) and the two color components - a and b. The a component contains the range of red (a+) to green (a-), while the second component b contains yellow (b+) through blue (b-) colors. Neutrals occur where a and b values are equal to zero. Thus, neutral mid-gray is L = 50, a = 0, and b = 0.
Although the Lab color space is a useful space for comparison between applications, it is a typical practice to supply output files in an RGB color space when further analysis and verification is required. Therefore, the displayed Lab values in Capture One are converted from the RGB color space selected as one of the parameters of the output Process Recipe. However, as color space profiles assigned to images for output can be interpreted differently by third-party applications when converting to Lab values, Capture One supports several Lab implementations to match the color management interpretations of these utilities.