About Blending Modes

There are 23 different blending options available from the Layers palette and a few additional ones that work with specific tools. How do they work? The simple answer is "It depends." Your response is likely "Depends on what?" Simply put, the effect achieved by blending two layers varies with the contents of those two layers. A blending mode compares the content of two layers and enacts changes based on the contents of both layers. You'll find blending modes in many of the tools and they can be combined with every filter.

The blending mode specified in the Options bar controls how pixels are affected by a painting or editing tool. Additionally, you can set the blending mode of a layer to control how it interacts with those below it. A clear understanding of the following terms will better help you understand blending modes:

• Base Color: The original color in the image

• Blend Color: The color being applied with the painting or editing tool (or the color in the top layer)

• Result Color: The color resulting from the blend

List of Blending Modes

Here are the different blending modes available through the Layers palette. I have attempted to give you a clear and simple definition as well as a sample of how these images blend.

Original

Blended Image

Dissolve

This creates a random replacement of the pixels with the base or blend color.

Darken

Pixels lighter than blend are replaced; darker ones are not.

Multiply

This is similar to drawing strokes on the image with magic markers.

Color Burn

This evaluates each channel; darkens base by increasing contrast.

Linear Burn

This evaluates each channel; darkens base by decreasing brightness.

Lighten

This evaluates each channel; it then uses base or blend color (whichever is lighter).

Screen

This results in a lighter color. It is useful for "knocking" black out of a layer.

Color Dodge

This evaluates color information and brightens base by decreasing contrast.

Linear Dodge

This evaluates color information and brightens base by increasing brightness.

Overlay

This overlays existing pixels while preserving highlights and shadows of base.

Soft Light

The effect is similar to shining a diffused spotlight on the image.

Hard Light

The effect is similar to shining a harsh spotlight on the image.

Vivid Light

This burns or dodges by increasing or decreasing the contrast.

Linear Light

This burns or dodges by decreasing or increasing the brightness.

Pin Light

This is useful for adding special effects to an image.

Hard Mix

This enhances the contrast of the underlying layers.

Difference

This evaluates each channel and subtracts depending on greater brightness.

Exclusion

This is similar to the Difference mode but lower in contrast.

Hue

This mode uses luminance and saturation of the base and the hue of the blend.

Saturation

This creates color with luminance and hue of base and saturation of blend.

Color

This mode preserves gray levels. It's very useful for coloring and tinting.

Luminosity

This is the inverse effect from the Color mode.

Open the file Blended_Overlay.psd from the Chapter 9 folder on the DVD-ROM to experiment with blending modes.

Blending Modes in Practice

So far we've looked at blending modes in a strictly technical sense. While it's useful to have a clear understanding of the technology, let's not lose sight of the design possibilities. Blending modes are a great way to mix layers together. For a designer, this can be a useful way to create backgrounds for speaker support (like PowerPoint presentations) or DVD menus. Let's dissect one of those backgrounds:

1.	Open the file Speaker Support.psd from the Chapter 9 folder on the DVD-ROM. This seven-layer document uses blending modes to create a complex background.
2.	Turn off the visibility icons for all but the bottommost two layers.
3.	Select the layer Train. It is currently set to the Overlay blending mode. Changing its blending mode will create a different look.
4.	A useful shortcut to cycle blending modes is Shift++(plus). This will step you forward in your blending mode list. Pressing Shift+- (minus) will step backward through the blending mode list. If you have a tool selected that has its own mode settings (such as the Brush or Gradient tools), the shortcut impacts the tool. To quickly change the mode on a layer, select the Move tool (V) or Marquee tools (M) first. Experiment with different blending modes and opacity settings to try out different looks.
5.	Repeat the blending mode experimentation for the Light, Highlights, and Soft Focus layers. Try out different modes and opacity settings. Note: Blending Mode Practice For more practice with blending, open the files Blend Modes 1.psd and Blend Modes 2.psd in the Chapter 9 folder and experiment with different modes and opacity settings.
6.	Select the layer Blue. It is set to the Color blending mode, which applies its color to all layers below it. This is a very useful way to tint multiple layers for a consistent look.

Feel free to continue to experiment with different combinations of blending modes and opacity settings. This sample image is just a quick glimpse into the power and flexibility of blending modes.

Design "Rules" for Blending Modes

Rule #1Don't try to memorize how each blending mode works: The good news is that they are grouped by similar traits. As you make your way through the list, you will notice a gradual progression through styles. The first group darkens your underlying image, whereas the second lightens it. The third set adds contrast, whereas the last two generate dramatic results by comparing or mapping values. Depending on your sources, some blending modes will generate little or no results. Sound confusing? Keep reading.

Rule #2Experiment: The best way to use blending modes is to just try them out. Clicking through a long drop-down menu is boring. A much better alternative is to select the Move tool and then use the Shift++ keyboard shortcut.

Rule #3Exploit them: Need a quick visual pop? Try blending a blurred image on top of itself. Need to tint something? Place a solid or gradient on top and change to Hue or Color mode. You'll find blending modes available to every filter (choose Fade Filter from the Edit menu) and all of your Brush tools.

Video Training

Blending Modes