So after the slight interruption from Totally Stylin’ Barbie last week, we’re back to our burgeoning series on the modern graphic designer’s best friend, non-destructive editing (especially if you can’t afford a graphic artist, and have to do it yourself). I believe so heartily in this concept that I hope I can dedicate several weeks to its exploration.

Layer masks are a wonderful creation where you can selectively apply transparency to a layer. So while this may at first seem the same task as the eraser tool, you should not confuse them. Actually, if you want to get more work done faster at a higher quality, you should actually consider abandoning your eraser all together (I’ll explain more about that later). Layer masks should in most cases be considered as part of an existing layer, and for this reason all graphic editing software I have ever used display them side-by-side with the layer that they are affecting. There are a lot of ways to explain them, like that they are the opposite of an actual layer, but instead of losing everyone, I think I will just jump to showing you what they do.

I understand that the above is likely hard to read, thus it links to the full size picture of layer masks. I right clicked the layer in the layer manager which brought up the context menu where there is an option to “Add Layer Mask.” Based on your selection in the next dialog box, you will end up with a white or black or other box that looks like a layer, but it’s place conspicuously next to the layer you clicked. Simply click the layer mask preview, to switch to editing the layer mask, not it’s corresponding layer.

Now, in layer masks, black means transparent, and white means opaque. In other words, white means that you can see that area of it’s affected layer, and black sections are turned invisible much like if you erased them.

There are a lot of reasons why this is nice. One, you can use gradients from black to white and vise versa to make awesome fading effects like you can see demonstrated in the picture. This is actually a very common need for web designers, and layer masks are the optimal way to do it. Two, as the series suggests, they are non-destructive, this means that if you are either painting black with a brush of any type or using a gradient and you are not happy with any of your work, you can simply try it again and again until you get it perfect with no loss to the image because keep in mind that you are only editing the layer mask, not the layer it is attached to. Finally, layer masks, once finished can be applied to the layer which actually makes permanent any changes in transparency which actually simulates an eraser, but with a hundred times the precision and flexibility. Layer masks can usually be deleted, applied, added, and hidden all from a context menu when you right click them.

I have included the two final logos of a fictional florist, the top with the layer masks turned off, and the bottom with the layer masks turned on. You can see a big difference, but you might be saying to yourself that you could have done that with an eraser and other permanent tools. That’s true, but if you want to see the full benefit of layer masks, I have included the GIMP file for download and see what you can do by maybe turning my smooth line layer masks into gradients, or changing my linear gradients into radial or shaped ones. If you take a second to think about how much time and effort that will save you, you will fall in love, as I have.

With layer masks

Without layer masks

PupilsIris.xcf (GIMP)