Julieanne Kost's Blog

The second group of Blend modes (Darken, Multiply, Color Burn, Linear Burn and Darker Color) have a Neutral color of white. This means that white as a blend color will have no effect on the result color (white simply disappears). These blend modes all have stronger effects as the blend color becomes darker. Using the Fill slider on Layers palette using blend modes from this group may modulate this effect rather than performing a simple opacity blend the way normal mode does. By definition:

• Darken – Looks at the color information in each channel and selects the darker of the base or blend color as the result color. Pixels lighter than the blend color are replaced, and pixels darker than the blend color do not change.

• Multiply – Looks at the color information in each channel and multiplies the base color by the blend color. The result color is always a darker color. Multiplying any color with black produces black.  When you’re painting with a color other than black or white, successive strokes with a painting tool produce progressively darker colors, producing an effect similar to drawing on the image with multiple magic markers. Multiply is a bit like sandwiching two chromes and projecting them together.

• Color Burn – Looks at the color information in each channel and darkens the base color to reflect the blend color by increasing the contrast. The result will always be darker and have more contrast.

• Linear Burn – Looks at the color information in each channel and darkens the base color to reflect the blend color by decreasing the brightness and – unlike multiply – it will clip values while doing so. It has a stronger darkening effect than either multiply or color burn. Linear Burn is a combination of color burn and multiply.

• Darker Color – Compares the total of all channel values for the blend and base color and displays the lower value color. Darker Color does not produce a third color, which can result from the Darken blend, because it chooses the lowest channel values from both the base and the blend color to create the result color.

The first image illustrates the leaf layer with it's blend mode set to Darken. The second illustration shows the result of Multiply, then Color Burn, Linear Burn and finally, Darker Color.

One common use of the Multiply blend mode is to add edge effects. Start with edges from one of many sources such as scanned torn or deckle edged paper, painted edges (painted either traditionally or in Photoshop) or purchase edges from one of many sources such as Graphic Authority and onOne Software. Position the edge at the top of the layer stack. In the first illustration (where the edges are black and the center of the image white), setting the blend mode to Multiply will keep the black edge and hide the white center (the results are shown in illustration #2). If you have white edges and a black center like the third illustration, change the blend mode to Screen to keep the white and hide the black (shown in illustration #4 - but now we’re getting ahead of ourselves...). Note: if your edges are the opposite of what you desire choose Image > Adjustments > Invert to invert the edge layer, then apply the necessary blend mode.

In previous posts, I have covered the shortcuts to change blend modes, and as a result, I have had several people request more detailed information about each blending mode so lets get started.

First some basic information – a blend mode allows you to control how the pixels on one layer work with or affect (or blend with) other pixels in Photoshop. They can be found throughout the program in such areas as the Layers panel, Layer Styles,  the Fill, Stroke and Fade commands, the Painting tools, and Apply Image and Calculations commands. Within each of these different areas of the program, the blend modes which are available vary based on which modes are useful and appropriate for each command. Except where noted, these modes work on a per channel basis — i.e., they treat an RGB image like three grayscale images.

When using blend modes, it’s helpful to think of the effects in terms of the following three colors:

• The base color is the original color in the image (which can be the color on a layer or a cumulative combination of layers).

• The blend color is the color being blended (the painting or editing color).

• The result color is the color resulting from the blend.

Note – some of the blend modes have what are called Neutral colors, or colors that have no effect when they are blended. For example, Multiply has a Neutral color of black, and Screen’s neutral color is white – but I’m getting ahead of myself…

The first grouping of blend modes contain from one to four blend modes depending on the feature: Normal, Dissolve, Behind and Clear. Note: the Fill command and the painting tools are the only ones that list the Behind and Clear blend modes. In this grouping, there is no Neutral color – all blend colors will effect the base colors. When used at 100% opacity, the blend color will replace the base color. I point out that I’m using 100% because lowering the opacity of the layer (or paint or fill etc.) will change the way that the blend color is combined with the layer below.  By definition:

• Normal – This is the default mode. Pixels don’t blend. Results are as expected – you choose red to paint with, and you get red. You put a photo on a layer and it is displayed as the original photo obscuring any layers beneath it. As expected. (Under the hood, this mode edits or paints each pixel to make it the result color. Note: Normal mode becomes Threshold when you’re working with a bitmapped or indexed-color image.)

• Dissolve  – Edits or paints each pixel to make it the result color; however, the result color is a random replacement of the pixels with the base color or the blend color, depending on the opacity at any pixel location. Lowering the opacity (in this case the opacity of the Layers palette) reveals a speckled effect which is either the blend color or the base color – never a combination of the two. I’ve seen this blend mode used effectively when creating a stippled effect with the paintbrush and a large brush (see illustrations below).

• Behind – Edits or paints only in the transparent areas of a layer. This mode is available for the painting tools and the Fill command.  It’s like painting on the back side of acetate, underneath the image. Note: this mode works only in layers with Lock Transparency deselected (that little checkerboard icon to the right of the word Lock on the Layers panel).

• Clear – Makes all affected pixels transparent – essentially the same result as using the Eraser tool. This mode is available for the painting tools, the Fill command, and the Stroke command. Note: you must be in a layer with Lock Transparency deselected to use this mode.

The first image is the original photo of the mountains. The second is photo of leaves with the background deleted. The third image shows the result of the leaves stacked on their own layer, on top of the mountains with the blend mode for the leaves layer set to Normal (in the Layers panel). The last image also has the leave's blend mode set to Normal, but the opacity of the layer has been reduced to 50%.

In the first image, the blend mode for the leaves layer is set to Dissolve. The second illustration is a painting of the leaves layer created by using the Clone Stamp tool with it's blend mode set to Dissolve (sampling from all layers, and painting on an empty layer). The third image shows painting with the Paint Brush tool (on the leaf layer) with the paint brush's blend mode set to Behind (basically Behind only allows paint to be added in the transparent areas). Note: most of the time I think it would just be easier to paint on a separate layer but I'm sure that people have reasons to do it this way! The fourth image also shows the paint brush painting (on the leaf layer), but with the paint brush's blend mode set to Clear (basically it acts as an eraser!).

Hue- Option (Mac)/ Alt (Win) + Shift + U
Saturation- Option (Mac)/ Alt (Win) + Shift + T
Color – Option (Mac)/ Alt (Win) + Shift + C
Luminosity – Option (Mac)/ Alt (Win) + Shift + Y

Difference- Option (Mac)/ Alt (Win) + Shift + E
Exclusion – Option (Mac)/ Alt (Win) + Shift + X

• Overlay – Option (Mac)/ Alt (Win) + Shift + O
• Soft Light- Option (Mac)/ Alt (Win) + Shift + F
• Hard Light – Option (Mac)/ Alt (Win) + Shift + H
• Vivid Light – Option (Mac)/ Alt (Win) + Shift + V
• Linear Light- Option (Mac)/ Alt (Win) + Shift + J
• Pin Light – Option (Mac)/ Alt (Win) + Shift + Z
• Hard Mix – Option (Mac)/ Alt (Win) + Shift + L

• Darken – Option (Mac)/ Alt (Win) + Shift + K
• Multiply – Option (Mac)/ Alt (Win) + Shift + M
• Color Burn – Option (Mac)/ Alt (Win) + Shift + B
• Linear Burn – Option (Mac)/ Alt (Win) + Shift + A

• Lighten – Option (Mac)/ Alt (Win) + Shift + G
• Screen – Option (Mac)/ Alt (Win) + Shift + S
• Color Dodge – Option (Mac)/ Alt (Win) + Shift + D
• Linear Dodge – Option (Mac)/ Alt (Win) + Shift + W

I have previously posted the shortcut to quickly move through all of the Blend Modes in the Layer’s panel (and/or for changing the blend modes for specific tools).But just in case you’ve forgotten it’s : Shift plus “+” (plus) or “-” (minus) to move down or up through the list. However I also mentioned that each Blend Mode also has it’s own shortcut (yet didn’t list them – so this week we’ll go through them).They all begin with the modifiers: Option (Mac)/ Alt (Win) + Shift + a letter. Most often the letter is the first letter of the name of the Blend Mode. Here are the shortcuts for the first grouping:
• Normal – Option (Mac)/ Alt (Win) + Shift + N
• Dissolve – Option (Mac)/ Alt (Win) + Shift + I
Note: The next two shortcuts are only associated with brushes, not layers.
• Behind – Option (Mac)/ Alt (Win) + Shift + Q
• Clear – Option (Mac)/ Alt (Win) + Shift + R

To help with the placement/alignment/scale of an object that is being “placed”, the (placed) layer’s opacity and blend mode can be modified in the layers panel. Note: a layer’s opacity, fill and blend mode can also be modified while being transformed (Edit > Free Transform).

Layer Groups have their own blend mode called Pass Through which allows blending and transparency options to “pass through” the group and effect any layers below the group. To isolate the blending of layers within a group, change the Group’s blend mode to Normal.

Layer Groups are, by default, set to display blending effects (such as opacity, blend modes etc.) just like any other layer in Photoshop. For example, if a layer in a Group has it’s blend mode is set to “Multiply”, it will be multiplied (blended) with all other layers below it. In this default state, clicking on the Group in the Layers panel displays “Pass Through” as the Group’s blend mode (i.e: any blending applied to layers within the group is “passing through” the group to be applied to the layers below it).

To change this default behavior to limit the blending between layers to only those layers within the Groups, target the Group in the Layers panel and set the Groups blend mode to “Normal” . For even more advanced blending of channels within Groups, choose Layer >Group Properties (or Control (Mac)/ right mouse (Win) -click the Group icon in the Layers panel and select Group Properties) to specify which channels to use for special effect blending of layers.

All blend modes have their own keyboard shortcut. They all begin with Option (Mac)/ Alt (Win) + Shift + a letter – most often the letter is the first letter of the name, N = Normal, M = Multiple, O = Overlay etc. If you want to quickly cycle through the painting tool’s blend modes, hold the Shift key and hit the “+” (plus) or “-” (minus) to move forward or backwards. Note: If you have a tool selected that is not a painting tool, these shortcuts will affect the blend modes on the Layers panel.

In this training video, (Creative Retouching Techniques and Edge Effects in Photoshop), you will discover how to to completely change the look and feel of a photograph with some simple retouching, creative adjustments, and the addition of edges and texture.

Explore several of the new tools in Photoshop CS3 in this video tutorial (The Creative Composite “Drifting”), as Julieanne Kost walks you though the creation of a digital composite she created based on a personal assignment for the concept drifting.