The « Lighten » group contains layer modes that make the result lighter.
À chaque point de l’image, la valeur maximum des pixels des 2 calques est affectée au pixel du calque actif. Les calques entièrement noirs n’ont aucun effet sur l’image finale et ceux complètement blancs donnent une image entièrement blanche.
The mode is commutative; the order of the two layers doesn't matter (except for transparent areas in the bottom layer).
mode compares the luminance of each pixel in the upper layer with the corresponding one in the lower layer and uses the larger value in the resulting image. Completely black layers have no effect on the final image and completely white layers result in a white image. Luma is the perceptual version of Luminance.
The mode is commutative; the order of the two layers doesn't matter (except for transparent areas in the bottom layer).
Screen mode inverts the values of each of the visible pixels in the two layers of the image. (That is, it subtracts each of them from 1.0.) Then it multiplies them together, and inverts this value again. The resulting image is usually brighter, and sometimes « washed out » in appearance. The exceptions to this are a black layer, which does not change the other layer, and a white layer, which results in a white image. Darker colors in the image appear to be more transparent.
Ce mode est commutatif : l’ordre des calques ne compte pas.
Dodge mode divides the pixel value of the lower layer by the inverse of the pixel value of the top layer. The resulting image is usually lighter, but some colors may be inverted.
En photographie argentique, cette technique est utilisée en chambre noire pour diminuer l’exposition de certaines parties de la photo, ce qui fait apparaître de nouveaux détails dans les zones d’ombre. Cette technique fonctionne mieux sur les images en niveaux de gris, et en utilisant un pinceau, plutôt que comme mode de calque.
Addition mode is very simple. The pixel values of the upper and lower layers are added to each other. The resulting image is usually lighter. The equation can result in color values greater than 1.0.
Ce mode est commutatif : l’ordre des calques ne compte pas.