UPDATE: Adobe (finally) included pixel layer masks in Elements 9, so I'm pleased to say that this workaround is no longer required. For users with older versions, this tutorial is still critically important.
The Problem
Photoshop Elements is a very powerful program, but it's a cut-down version of Photoshop, and there are quite a few functions missing. One of these is masks for pixel layers.
Let's get something very clear at the outset: Elements has masks, but only on adjustment layers, not pixel layers.
Some people think that Elements doesn't have any kind of masking capabilities - if that were true, it would be practically useless. I'm pleased to report that it has masks on adjustment layers just like Photoshop, and frankly, adjustment layers are where you need masks 95% of the time.
Here's a Levels adjustment layer in Elements. See? A fully-functional layer mask.
As long as you adhere to a non-destructive workflow, most of your work is done with adjustment layers. But pixel layers (and their masks) are necessary for things like:
> Selective sharpening
> Complex cloning
> Noise reduction
> Skin smoothing
> Headswaps
> Collages
> etc ...
In a full version of Photoshop, masks can be applied to any layer with the click of a button. In this example, you can see a High Pass Sharpen layer masked to only affect one subject:
To mask a pixel layer in Elements, you need to clip it to an adjustment layer, and use the adjustment layer's mask.
Step 1
Make your pixel layer as required.
In this example, I've used another High Pass Sharpen layer.
Step 2
Make an adjustment layer immediately below the pixel layer. Don't make any adjustments to the layer.
I usually use a Brightness/Contrast layer, simply because I never use those stupid things for anything else.
Step 3
Rename that layer to clarify its purpose (this is optional).
Step 4
Hold down the Alt/Option key and position your mouse precisely between the mask layer and the pixel layer.
At this point the mouse pointer will change to look something like this ...
... and when you click, the layers will be linked together like this:
Step 5
Paint on the mask of the adjustment layer, and it will mask the linked pixel layer. Easy!
Another example
In this photo, I wanted to move one person to sit closer to the other. So I copied one person onto his own layer, moved him across, then linked a mask layer to blend him in:
Groups of layers
In Photoshop, you can put multiple layers together in a Layer Group, and mask the group. This is very handy if you want to make several different adjustments to the same area of a photo:
In Elements, it's not quite so easy, but similar control is possible. You just need to Alt-click between all the layers so they are all linked to the bottom mask layer:
Elements add-ons
There are various third-party add-ons available for Elements which give it advanced functionality, including pixel layer masks. If you frequently need to mask pixel layers, or group multiple layers, it might be a very good idea to investigate these options, and purchase something that suits you.
But for occasional use, the method I've described here will serve you well.
If you have a question about this tutorial, or any Photoshop question, please visit me at my "Ask Damien" Facebook page.
All content © Damien Symonds 2012