Kreft's dichromaticity index

The two hue angle differences are called the dichromaticity index towards lighter (Kreft's DIL) and dichromaticity index towards darker (Kreft's DID) respectively.

This means, that pumpkin seed oil changes its color from green-yellow to orange-red (for 44 degrees in Lab color space) when the thickness of the observed layer is increased from cca 0.5 mm to 2 mm; and it changes slightly towards green (for 9 degrees) if its thickness is reduced for four-fold.

The color of pumpkin oil at increasing thickness or concentration presented in CIELAB colorspace diagram.

Straight lines are vectors showing hue (angle) and chroma (length) of the color at maximal chroma (toward the square mark), and the colors of four-fold less or more diluted or thick pumpkin oil (DIL and DID).

Dichromaticity (DIL and DID) of selected substances, calculated from their VIS absorption spectra by the computer algorithm “Dichromaticity index calculator”: Maximal chroma: chroma at concentration (thickness) where the color of the substance has maximal chroma (saturation).

Presentation of the changing color of pumpkin oil (in the CIELab color space) as its thickness or concentration changes