Matching Lab Conversion to Third Party Software

Capture One Pro offers several Lab implementations to match the different interpretations of RGB profiles by third-party applications.

Conversion options

As previously discussed in this guide, most profiles can be interpreted in different ways which will lead to the Lab conversion results, and therefore color values, being different to the those displayed in Capture One. To obtain the same results as a third-party application, it is necessary to select an interpretation in Capture One that matches that of the target analyzer software you intend to use.

Although Capture One supports a number of variations used by third-parties, in some cases it may also be necessary to configure the analyzer software. It is usually necessary to disable Black Point Compensation (BPC) for color space profiles that are unable to represent black. Note that some applications enable BPC when the perceptual intent is selected, regardless of other settings to the contrary.

Generic conversion

Capture One provides two generic conversion options. The Generic D50 option matches most third-party implementations such as that used by Delt.ae by Picturae and LCMS by Marti Maria, and converts Lab values using D50 as the white point.

Generic (media white) can be used to match colors while avoiding chromatic adaptation. However, colors must be measured under the light source of the intended color space profile. For sRGB and Adobe RGB (1998) this is D65.

Adobe Photoshop

Two further options are offered for use with Adobe Photoshop and compatibility with the Adobe Color Engine (ACE). Capture One does not support Black Point Compensation (BPC). In third party applications, this is often achieved using a linear transform on individual XYZ-values, which doesn’t preserve accurate colors. Therefore, it is necessary to disable this option, where posible. Note also that, Adobe Photoshop enables BPC when Perceptual rendering intent is selected, regardless of other settings, therefore it is recommended to select Relative Colorimetric instead and disable BPC and enable Use Dither.

ISA GoldenThread

Popular within the digital archiving industry, GoldenThread analysis software by ImageScience Associates is capable of analysis using either an ICC profile or directly using a standard color space.

To compare readouts in an image with an ICC profile, select GoldenThread (ICC), otherwise select the GoldenThread (standard) option. Note that, the output profile in Capture One must match the option used in the analysis. While GoldenThread will not use the profile directly in the Standard mode, Capture One must still apply the conversion to the correct color space.