About Blending Mode

  In this tutorial, I’m going to give you an in-depth explanation of how the Blending Modes (Blend Modes) in Photoshop work.

You may have worked with Blending Modes in the past, and it was probably more of an experimental process for you.

The purpose of this tutorial is to show you how exactly how each Blend Mode works, so you don’t have to experiment as much.

By the time you finish watching this Photoshop tutorial, you should have a strong understanding of how Blending Modes work and which to use to get your desired effect.

Blending Modes or Blend Modes?

Officially they are known as Blending Modes, but you can use the names interchangeably. I sometimes refer to them as “Blend Modes,” so no worries as to which name you use. As longs as you know how they work!

Opacity vs. Fill With Blending Modes

19 out of the 27 Blending Modes behave the same way when Fill is adjusted, compared to when Opacity is adjusted. However, eight Blending Modes give you a different result when Fill is changed compared to Opacity.

It is crucial to understand the difference because this additional method of blending pixels extends the capabilities of Blending Modes. More importantly, the blend tends to be more aesthetically pleasing when using Fill rather than Opacity with these eight Blending Modes.

In the example below, you can see how a graphic with different luminance values and a photo of Venice were blended using the Hard Mix Blending Mode. The image in the center is set at Opacity at 50%, while the image on the right is set to Fill at 50%.

The Blending Modes that are part of this group of 8 are Color Burn, Linear Burn, Color Dodge, Linear Dodge (Add), Vivid Light, Linear Light, Hard Mix, and Difference.

“Transparency Shapes Layer” Check Box

The 8 Blending Modes in this group, also give you an extra level of blending by un-checking the “Transparency Shapes Layer” checkbox in the Layer Style panel.

In the example below, you can see how Linear Light blends differently when “Transparency Shapes Layer” is unchecked. Notice how the edges of the circles blend differently on the example on the right.

Base + Blend = Result

You should remember these three terms to understand how Blending Modes work.

The “Base” color is the original color in the image.

The “Blend” color is the color applied with the painting or editing tool to the Base layer.

The “Result” color is the color resulting from the blend.

How the Base and the Blend colors mix depends on the algorithm or Blending Mode that you select.

Blend Mode Math

For those of you who are interested in how the math behind Blend Modes work, I’ve created a simplified explanation.

Photoshop uses “Standardized” values to calculate the blend. The luminance values in Blending Mode math range from 0 (black) to 1 (white). However, Photoshop uses 0 (black) to 255 (white) to represent luminance values in RGB. Photoshop has to convert the values, so black is still 0, but white becomes 1. 50% gray which is 128 becomes 0.5.

To convert an RGB luminance value to a standardized value, dive it by 255. For example, divide 192 (light gray) by 255, and you get 0.75 (192÷255=0.75).

Math Sample:

A = Blend Layer Standardized Value
B = Base Layer Standardized Value

Multiply:
AxB = Result

Color Dodge:
B÷(1-A) = Result

Adobe provides descriptions on each Blending Mode, but they do not provide the mathematical equations behind them. If you would like to find out more about Blending Mode math, check out the Wikipedia page on Blend Modes.