Layer Masks & Adjustment Layers

1. Layer Masks

Adding a mask to a layer helps to hide portions of the layer without deleting any pixel information. Here's how to do that.

• Layer masks are non-destructive. The new thumbnail next to the layer's thumbnail represents the grayscale channel that is created when you add the layer mask;
• You can edit a layer mask to add or subtract from the masked region. The areas you paint in black are hidden, the areas you paint in white are visible, and the areas you paint in shades of gray appear in various levels of transparency;
• Clicking on the letter "D" on your keyboard brings the colors to default: black as a foreground color, and white as a background color. In the mask layer, it's inverted. White is the foreground color, and black is the background color;
• To make a quick layer mask, make a selection of the parts of a layer you want to show. Then create a new layer mask from the bottom of the layers panel;
• If your layer mask isn't a perfect fit, open it in Photoshop's Select and Mask workspace to refine the mask similar to how you do it with regular selections;
• By default, a layer is linked to its layer mask with the link icon between the thumbnails in the Layers panel. The layer and its mask move together in the image when you move either one with the Move tool. Unlinking them lets you move either of them independently and shift the mask's boundaries separately from the layer;
• A red X appears over the mask thumbnail in the Layers panel when the mask is disabled, and to delete a mask, press the right mouse button over the layer mask thumbnail and choose Delete Layer Mask.

2. Adjustment Layers

• To make adjustments to image layers, start by selecting an image layer and going to Image > Adjustments in the menu bar. Note that this method doesn't allow for future edits without starting over;
• Instead, create a new adjustment layer by clicking the icon at the bottom of the Layers panel and selecting the adjustment you want. This creates an extra layer that can be edited via the Properties panel;
• The adjustment layers affect all layers below them. But to apply adjustments to individual layers, use a Clipping Mask;
• A clipping mask in Photoshop is a feature that allows one layer to control the visibility of another layer. The layer on top, which is the "clipping" layer, takes the shape of the layer directly below it, known as the "base" layer. This means that the content of the clipping layer is only visible where it overlaps with the non-transparent areas of the base layer;
• To create a clipping mask, click the right mouse button on the adjustment layer and select Create Clipping Mask or hold the Alt key (Windows) or Option key (MacOS) and click between the layers.

Utilizing All Tools

Let's put all the tools and skills that we’ve learned so far together in a couple of projects.

• With the first one, you'll see how to change the mood and colors of an image.
• With the second one, you'll learn how to change the background of an image, and blend it perfectly with the new added background.