Keetee

Today’s lesson is an introduction to masking, a Photoshop tool that can make working on multiple layers really efficient. In this tutorial, we’ll be using a mask to change the backdrop of a photo. This is an easy one, but will lay a good foundation for using this technique on more complex works.

Final Image Preview

Assets

This cute little turtle is brought to us by Shiev. You may download it here if you’d like to work with the original file.

The Process

Our first step is to indicate which area of our photo we want masked.

Select the Polygonal Lasso Tool from the Tools panel. (If you only see the Lasso Tool, click and hold the Lasso Tool button to show other options in the same category. Then select Polygonal Lasso Tool from the sub-menu.)

Use a series of clicks to outline the subject of your image. (In other words, the area you do not want to hide.) It doesn’t have to be exactly perfect—we’ll clean things up later—but try to be precise.

Next, open the Masks panel by going to Window » Masks. Click the Select the Pixel Mask button.

Here’s the result. The area that you did not select is now hidden.

You’ll also notice your layer has changed. The black-and-white box is your Layer Mask. The black areas are hidden (”masked”), and the white areas remain visible.

Now that we’ve hidden the background, we can add in one of our own. I’m going to use a free texture I downloaded awhile from Bittbox, but anything will do!

Create a new layer and place it below your photo. Paste your background into this layer.

I see some rough edges—tiny parts of the old backdrop—on the top of my turtle’s head, so I’m going to fix that. Adjusting your layer mask is easy.

First, click on your Layer Mask:

Any area you paint in black will be masked. So, we’re going to use a black brush to hide the little excess backdrop peeking through.

Select an appropriately-sized brush, 100% hardness, and black. I used 9px, but if your image is larger, you may need a larger brush. Then, brush over the areas you want invisible.

If you hide too much, just switch your brush to white. Anything you paint in white will show!

Ta-da! We’re just about done. The last thing I want to show you is that you can still apply Blending Options to masked layers. What if we want a little drop shadow on Mr. Turtle? Easy!

Right-click your original photo layer and select Blending Options. Check and click on the Drop Shadow menu item, then adjust the settings to this:

Final Image

Just for fun, here’s our turtle in space!

Any questions about this tutorial? Lay ‘em on me in the comments! :)