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Before reading this section, be sure to read the material on Curves.
Create blends with two layers: a top blend layer and a bottom image layer. Select blend mode in the Layers palette, or as an option with the Clone and Pattern Stamp tools.
All blends operate on each color channel individually. For example, the Lighten blend chooses the lightest color between the blend and image layers. This is done by examining pixel values for each channel, and choosing the lightest value for the red, green, and blue channels. For example, if you blend pixel (96,128,192) with image pixel (190,128,96), the final result will be (190,128,192). Blending modes are grouped by functionality in the drop-down menu.
Blends are grouped in the Photoshop drop-down menu by category.
Type Blend Effect Darken Darken
Multiply
Color Burn*
Linear Burn*Blend values less than 255 darken.
White or transparent blends have no effect.Lighten Lighten
Screen
Color Dodge*
Linear Dodge*Blend values greater than 0 lighten.
Black or transparent blends have no effect.Darken & Lighten Overlay
Soft Light
Hard Light
Vivid Light*
Linear Light*
Pin Light
Hard Mix*Blend values less than 128 darken.
Blend values greater than 128 lighten.
Gray (128,128,128) or transparent blends
have no effect.
For all blends, adjusting the Opacity slider controls the amount of the blend. For blends marked with an asterisk (*), adjusting the Fill slider controls the intensity or contrast of the effect. The following section examines several blends in detail.
Lighten
For each pixel, both layers are examined and the pixel with the lightest value is chosen. Lighten
is a good choice when retouching blemishes in a portrait. After selecting the Clone tool, choose a
Lighten blend in the Options bar so that the stamp will lighten darker areas around the blemish and
leave lighter areas untouched.
Darken
For each pixel, both layers are examined and the pixel with the darkest value is chosen.
Pin Light
A combination of Lighten and Darken blends. Values greater than 128 Lighten and values less than
128 darken.
Color Dodge
Grayscale values in the blend compress tonal values to lighten the image. The effect is similar to
changing the white point in Levels. Colored Dodge simultaneously lighten and passes colors to the
underlying image layer.
Color Burn
Grayscale values in the blend compress tonal values to darken the image. The effect is similar to
changing the black point in Levels. Colored Burn simultaneously darkens and passes colors to the
underlying image layer.
Hard Mix
A combination of Color Dodge and Color Burn. Values greater than 128 dodge and values less than 128
burn. This blend is used in conjunction with grayscale values for the Paint
with Light action.
Multiply
Multiply darkens an image. A white or transparent blend has no effect. Paint the blend with shades
of gray or black to darken the image. A black blend produces pure black in the final image. Most of
the effect is confined to high values that are mapped, in a linear fashion, to lower values. For
example, a blend filled with tonal value 192 will depress the right side of the curve to 192.
Blend an image with itself for a nonlinear decrease in brightness. Alternatively, add an Adjustment layer (any will do) with default settings. Change blending mode to Multiply and adjust Opacity to control brightness. The latter technique results in smaller files as we're just saving adjustment instructions rather than duplicating the entire image. Although tonal values are compressed, they are not truncated so detail loss is minimal. Multiply, with equivalent curves adjustments, is illustrated below.
For the mathematically inclined multiplying an image with itself alters pixel values as follows:
0 --> 0x0/255 = 0 16 --> 16x16/255 = 1 32 --> 32x32/255 = 4 64 --> 64x64/255 = 16 128 --> 128x128/255 = 64 192 --> 192x192/255 = 145 255 --> 255x255/255 = 255
Screen
Screen lightens an image. A black or transparent blend has no effect. Paint the blend with shades
of gray or white to lighten the image. A white blend produces pure white in the final image. Most
of the effect is confined to low values that are mapped, in a linear fashion, to higher values. For
example, a blend with tonal value 64 will raise the left side of the curve to 64.
Blend an image with itself for a nonlinear increase in brightness. Alternatively, add an Adjustment layer (any will do) with default settings. Change blending mode to Screen and adjust Opacity to control brightness. The latter technique results in smaller files as we're just saving adjustment instructions rather than duplicating the entire image. Although tonal values are compressed, they are not truncated so detail loss is minimal. Screen, with equivalent curves adjustments, is illustrated below.
Hard Light
Hard Light combines both Multiply and Screen. A gray (128,128,128) or transparent blend has no
effect. Paint with white to lighten and black to darken. Dark values result in a double-strength
Multiply blend, and light values result in a double-strength Screen blend. For example, a blend
with a tonal value of 96 (128 - 32) will lower the right side of the curve to 192 (256 - 2x32). A
blend with a tonal value of 160 (128 + 32) will raise the left side of the curve to 64 (2 x 32).
Although tonal values are compressed and expanded, they are not truncated so detail loss is
minimal. Hard Light, with equivalent curves adjustments, is illustrated below.
Overlay
Overlay lightens or darkens an image. A gray (128,128,128) or transparent blend has no effect.
Paint with white to lighten and black to darken. Blend an image with itself and light tones Screen
or lighten light tones, and dark tones Multiply or darken dark tones.
The result is a classic S-shaped curve for increasing contrast. Alternatively, add an Adjustment layer (any will do) with default settings. Change blending mode to Overlay and adjust Opacity to control contrast. Although tonal values are compressed and expanded, they are not truncated so detail loss is minimal. This technique works great in actions and is used in the Black & White action. Overlay, with equivalent curves adjustments, is illustrated below.
Soft Light
Soft Light is a low-strength version of Overlay.
Linear Light
Values that deviate from neutral gray are added/subtracted from image values. A blend with a tonal
value of 96 (128 - 32) subtracts 64 (2x32) from pixel values. A blend with a tonal value of 160
(128 + 32) adds 64 (2 x 32) to pixel values. Linear Light results in changes that are identical to modifying Brightness (Image > Adjustments > Brightness).
Detail loss occurs for truncated values.