There are some infrequent situations that still can lead to problematic results unless the user takes some action. Some modules in Lab color space rely on the fact that the L channels carries all lightness information, with the a and b channels purely representing chroma and hue. Unbounded colors with negative L values are especially problematic to these modules and can lead to black pixel artifacts.
On a constaté que des sources de lumière bleue hautement saturées dans l’image sont des candidats probables pour des pixels ayant des valeurs de L négatives. Si vous êtes engagé dans la photographie de spectacle, vous devez prêter une attention particulière à ces lumières apparaissant dans les images.
In order to mitigate this issue the input color profile module has a gamut clipping option. This option is switched off by default but can be activated if artifacts are observed. Depending on the settings, colors will be confined to one of the available RGB gamuts. In effect black pixel artifacts are prevented at the costs of losing some color dynamics.