An Overview of Blend Modes

Setting the blend mode of a layer effects how it is combined with the composite image formed by all the images below. The following examples illustrate the effect of different blend modes applied to an active (upper) layer of a blue radial gradient applied over an image of a masonry wall.

Lower Image	Upper Layer
Normal 100%	Normal 50%
Normal mode uses a weighted average to combine the pixel values, based on the transparency of the upper layer.
Dissolve 100%	Dissolve 50%
In dissolve mode, the pixels in the upper layer are randomly removed according to the transparency.
Multiply 100%	Multiply 50%
Multiply mode has the same effect as placing transparencies of the image back to back. It always darkens an image.
Screen 100%	Screen 50%
Screen mode has the same effect as projecting slides of the two images on the same screen. It always lightens an image.
Overlay 100%	Overlay 50%
Overlay mode gives the effect that the upper image is painted on the lower image, since the highlights and shadows of the lower image show through. It multiplies where the lower image is darker, and screens where the lower image is lighter.
Soft Light 100%	Soft Light 50%
Soft light is similar to overlay, but is more subtle and deemphasizes the color of the upper layer. It lightens the lower image when the upper layer is lighter than 50% grey and darkens the lower image when the upper layer is darker than 50% grey.
Hard Light 100%	Hard Light 50%
Hard light is similar to overlay, but gives more weight to the upper layer and its color. It multiplies when the upper layer is darker than 50% grey and screens when the upper layer is lighter than 50% grey.
Color Dodge 100%	Color Dodge 50%
Color dodge multiplies the brightess of the lower image according to the brightess of the upper layer. Like screen mode, it always lightens an image.
Color Burn 100%	Color Burn 50%
Color burn increases the darkness of the lower image based on the darkness of the upper layer. Like multiply, it always darkens an image.
Darken 100%	Darken 50%
Darken mode compares the values of the upper and lower image and chooses the darker value.
Lighten 100%	Lighten 50%
Lighten mode compares the upper and lower images and chooses the lighter value.
Difference 100%	Difference 50%
Difference mode inverts the lower image acccording to the brightness of the upper image.
Exclusion 100%	Exclusion 50%
Exclusion mode works like difference except it maps mid-tone pixels to neutral grey.
Hue 100%	Hue 50%
Hue mode uses hue from the upper layer, getting saturation and luminosity from the lower layer.
Saturation 100%	Saturation 50%
Saturation mode uses the saturation from the upper image, and hue and luminosity from the lower layer.
Color 100%	Color 50%
Color mode uses hue and saturation from the upper image, getting luminosity from the lower image.
Luminosity 100%	Luminosity 50%
Luminosity mode uses luminosity from the upper image, getting hue and saturation from the lower image.

Overlay mode is well suited to grafitti, since it allows the upper layer to take on the shadow and highlight characteristics of the lower layer.

Using Blend Modes in Photographic Work