Learning how to use Blend If in Photoshop opens up countless doors for seamless image blending in your edits. This feature allows you to blend two layers together using the luminance of one of the layers as a guide. This will enable you to blend a layer based on the shadows, midtones, or highlights separately or all together at varying degrees.
While the function may sound highly complex, it’s actually quite simple, although finding the right blend amount may take some practice. However, once you master this blending option, you can create several effects, such as blending text into photos or adding a gradient to only the highlights in an image.
Here is all you need to know about the function, with some valuable tips to help you get the most out of it and elevate your photos.
What Is Blend If In Photoshop?
The Blend If feature in Photoshop is a precise way to add exposure, color, or lighting effects to only the shadows, midtones, or highlights of the image. For example, this allows you to add a gradient to the highlights in the photo without adding the gradient to the shadows.
Blend If offers more control and better results than the standard blending modes in Photoshop.
In more detail, the Blend If function blends two layers together by masking one layer over the other based on the luminosity (brightness level of a color) values of a grayscale, red, blue, or green color channel.
While the Blend If feature may seem complicated if you are unfamiliar with it, once you learn the fundamentals and play around with the sliders a bit, you’ll realize the potential of this under-used feature.
When working with Blend If, in most cases, you will get the best results using the Grayscale color range and adjusting the Underlying Layer slider. However, I will explain the different options at the end of the process.
Use Blend If whenever you want to control the blending of two layers based on the luminosity range. You can also use this feature to blend brush strokes into an image or project.
How To Use Blend If In Photoshop
There are several ways you can use Blend If in Photoshop. You can add text to a textured background photo, such as a wall, and blend the text layer into the background to make it look like the text was painted on the wall.
Another popular use is to blend a gradient layer to add color or lighting effects to an image, which I will demonstrate by adding a yellow gradient to only the sky in this image of a model in a cornfield to create a sun glow effect.
Step 1: Add A Gradient Layer To The Image (Or Any Adjustment)
Once you have your base image in Photoshop, which you want to add the effects to, you can add your adjustment layer. For this example, I will add a gradient fill layer to make a sun glow effect. However, you can use any adjustment you’d like.
To add a gradient, click on the Create new fill or adjustment layer icon and select Gradient (or any other adjustment).
Step 2: Edit The Adjustment Layer Settings
You can now edit the adjustment settings to create the effect you are going for. Remember that the adjustment will cover the entire layer for now, and later, you can mask out the areas you don’t want to be affected.
In the gradient example, you can edit the color of the gradient by clicking on the gradient editor in the window that appears when adding the gradient fill layer.
In the Gradient Editor, you can then use the color stops to add the color you want for your gradient. Click OK when you have the color(s) you want for your gradient.
You can then adjust the gradient style, angle, and any other settings you need to. Click OK in the Gradient Fill window when you are happy with your gradient.
You will now have the gradient over the entire image layer, as by default, Photoshop adds the effect to the shadows, midtones, and highlights. You can now use Blend If to isolate this effect to a specific luminosity range.
Step 3: Open The Blending Options Panel In Layer Styles
To access the Blend If function, open the Layer Styles Panel. You can open the Layer Styles by clicking the fx icon at the bottom of the Layers Panel and selecting Blending Options.
You can also open the panel by double-clicking on the adjustment layer in the Layers Panel.
The Layer Styles Panel will open, and you will be in the Blending Options tab. The Blend If settings are located near the bottom of the panel.
It’s always a good idea to turn on the Preview option to view the changes on your image as you adjust the blending settings. To turn the preview on, click on the box next to Preview on the right-hand side of the panel. The checkmark shows that the preview is turned on.
Step 4: Set The Blend If Option To Gray
You can set the Blend If option to Gray, Red, Green, or Blue. If you select a color channel, the blending effect will work based on the selected color channel. If you choose gray, the blending effect will work based on the luminance values. In most cases, you should leave this set to Gray.
Step 5: Move The Underlying Layer Shadows Slider Inward
You can now begin the blending process using the Blend If sliders. Typically, you only use the Underlying Layer slider for the best results. However, I will explain the difference between the two sliders in the next section, as there are some cases where you’ll use the top slider.
To blend the effect into the image layer, move the shadow (black) or highlight (white) slider inward. If you want to remove the effect from the shadows, then pull the black slider inward. If you want to remove the effect from the highlights, adjust the white slider.
For this example, I will drag the black slider towards the white slider to remove the gradient from the shadows and midtones while keeping the effect in the highlights.
You will notice the blend may be harsh on the image when you move one of the sliders inward. This is because the blend doesn’t have any feathering. While only moving the entire slider will work on certain photos and effects, in some cases, you will need to feather the effect.
Step 6: Feather The Blend If Effect
If the blending effect is too harsh, you need to feather the effect. To feather the blending, hold in Alt (Win) or Option (Mac), click on the slider, and drag it. When holding in Alt/Option, the slider will split in two and feather the effect. The further apart the two slider halves are, the more feathered the effect becomes.
You can keep adjusting the slider(s) while viewing the changes on the image to blend the effect in as needed. You can move the shadows and highlights sliders inward if you only want the adjustment to affect the midtones.
In this example, I want the gradient only to affect the highlights in the image with a feathered effect, so I only need to adjust the shadows slider as in the example below.
The gradient is now blended into the image, which is the underlying layer. You can access the Blend If option and adjust it anytime by double-clicking on the layer to open the Layers Styles Panel.
In my image, you can see the yellow gradient is only visible in the highlights, which is mostly the sky, to create a sun glow effect.
Current Layer Vs. Underlying Layer Blend If Sliders
When using Blend If, you can adjust the visibility of a layer’s shadows, midtones, or highlights based on the exposure of the active layer or the layer below the active layer.
To blend the effect using the active layer, use the Current Layer slider. When using this slider, you will only make changes to the current selected layer. When adjusting this slider, you will set what luminance range of the current layer will be visible. Moving the shadows slider will remove the dark areas of the current layer, while moving the highlights slider does the opposite.
The top slider works well when removing a background from an image to place it on top of another photo. You can use the slider if your subject has a different luminance value to the background.
Note: The Current Layer slider is called “This Layer” in older versions of Photoshop.
The Underlying Layer slider determines what luminance range of the layer(s) below the active layer will be affected by the above adjustment. You can use this slider in instances such as the above example. Moving the shadows slider will remove the adjustment effect from the shadows in the below layer while leaving the effect visible in the highlights and vice versa.
As a result, adjusting the Underlying Layer slider causes areas of the layers below the active layer to show through based on the luminance values.
When working with both sliders, the luminance values outside the sliders (on the right of the highlights slider and the left of the shadows slider) will become invisible, meaning that the effect won’t be visible in those ranges.