How to Key a Background in Photoshop

Post by Elisabeth TenBrink Kelley, co-founder

     Something often used in film is "keying" a color. This is what they do with green screen. They make the background one color, and then key that color, and remove it, leaving it clear, which allows them to insert something else. Now, it can also be useful to photographers and graphic designers, as it was to me just yesterday, so I'll explain how to do it. Now, I use CS5, but certain earlier versions do work, and later ones certainly do, but I'm not certain which ones.

     So, the first thing is to have a picture with a distinct background. It doesn't have to be perfectly one color, but the closer the better. Here's my example:

     Seeing as this is a computer-made image, the background is very distinct, but with photos it will likely not be, so try to fix that as much as you can. Before we can move on, you need to make use that your primary color is the same as the background, so get the "eyedropper" tool and click your background. It looks like this:

     Next, we go to "Select" in the tool bar and click "Color Range", which is highlighted in blue below.

     Once you do, you will see a window like the one below, which will show you what is selected. (The white is selected, not the black) Adjust the "Fuzziness" until it covers the background well, but not the subject. You can also choose other preview options, which change the appearance of your image, not the black and white preview in the window.

     Once everything you want to get rid of is selected, press "OK" and you will be left with this:

     However, before you can remove the background, you need to make sure that your layer isn't locked. Background images are by default locked, and if you only have one layer, then it is automatically a background. It see if your layer is locked, look for the little padlock next to it.

     If it has one, just click and drag it to the little garbage can at the bottom of the "Layers" window. With that done, make sure everything you need is selected, and press "Delete".

     You should be left with something like this; a clean image ready to receive a new background. There are other ways of removing backgrounds, but this is the quickest and simplest, as long as you don't have anything of the background's color in the subject. If you do, the "Lasso" tool would probably work better.

Elisabeth TenBrink Kelley is an aspiring author and poet who likes to tinker with things in Photoshop. You can learn more about her in our About Us page.