Adding layer masks in Photoshop is a simple yet effective procedure, allowing you to blend several images together seamlessly. We show you how in our Photoshop courses.
First create a new document, choosing either for Web or Print. Note the various Preset sizes in each category.  The example here is a web banner 720 x 480 pixels, with a resolution of 72 ppi.
Then open three images. Go to Window > Arrange > Tile, in order to see the 4 documents on the screen. Hit F a few times to change Screen Mode. Then use the Move tool (V) to click & drag each image into your blank canvas. Then close the 3 image files. Note that you now have 3 new layers in your Photoshop document. Rename the layers by double-clicking on their titles.
Note at the bottom of the Layers panel there’s a button named Add Layer Mask – click this for the top 2 layers – a white square icon appears on the layer – this is the layer mask. The principle of masks is that black hides & white reveals. So by painting black onto the mask we will hide that part of the image. Choose the default black & white colours at the bottom of your Toolbox (D is the keyboard shortcut). Then select the Brush tool (B) & a large, soft-edged brush – eg. 200 px (top left of Control panel) and paint on the image. Note that a small black area will be painted onto the mask icon – this is the hidden part of the image. To adjust the mask, simply switch to white (X is the keyboard shortcut), and paint on the image again. It’s best to use the edge of a large brush rather than the centre. Repeat for the next layer down.
Save the file as a Working Copy (PSD) and when you are happy with the result, go to File > Save for Web, and choose one of the options.
Many more tips and techniques can be found at the Adobe website. And see many examples of our clients’ work on our Facebook page.
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