The option to initialize to Black shows that the mask will make the entire layer fully transparent.įor the purposes of this tutorial, we will let the mask initialize to White (full opacity).

Notice that the first option is to set the entire mask to White, which will result in full opacity on the layer (no transparency from the mask). There are many options for initializing the Layer Mask. This will then bring up the “ Add a Mask to the Layer” dialog with some options: You can also add a layer mask through the menus: Right-Click on the layer you want to add a mask to (the “Teal” layer in my example), and the Context menu will show an option to Add Layer Mask…: The teal layer is the active layer (look for the white border), and the one which we will add a layer mask to.

There is a base image at the bottom of the stack, and a single layer of teal over it. The process for adding them is simple.įor this example I will use a simple image with only two layers, as shown above. Layer masks need to be added to a layer before they can be used. This flexibility to define the opacity of different areas of a layer is the basis for more interesting image manipulation techniques such as selective coloring and luminosity masking. This modification of a layer’s transparency through a mask is non-destructive to the layer itself. This differs from the use of the layer Opacity slider as a mask has the ability to selectively modify the opacity of different areas across a single layer. They allow you to selectively modify the opacity (transparency) of the layer they belong to.

Layer masks are a fundamental tool in image manipulations.

Gimp tutorials photo editing layers