Background Eraser Tool: One of Photoshop’s Most Useful Tools
Photoshop is an image editing software that allows users to user an array of tools to change pretty much any aspect of a photo desired. With tools like dodge, burn and sponge you can strip color from objects, lighten them or darken them. With tools like the eye dropper you can grab the exact color from an image and use it to replace another color of the photo. It’s great, makes things super easy on you so you can just worry about being creative and getting the project done without any complications.
However, if you are a Photoshop newbie all the talk about tools and layers can seem a bit overwhelming. Take this Photoshop 101 course to get the lowdown on this awesome program.
If you are at all familiar with the way the color replacement tool works then this tutorial is going to be a breeze for you. If you’re not, stick with me until the end and you’ll have the basic idea of how to use that Photoshop feature, too.
Background Eraser Tool
I find it often that I, or someone I know, needs to get rid of the background of an image. Maybe you’re trying to create a super sweet Internet meme or you need a portion of an image for your logo – but you just can’t get rid of the background. Not only will this guide explain how to get rid of the background, it will teach you how to make the background transparent so you don’t get stuck with another background in another color (white).
Alright. We’re ready to get started now. I’m going to cut out the background of this sloth bomb photo because, while it’s hilarious, I think it’d be even better if sloth-man was on his own for whatever picture I need may need to, you know, sloth-bomb. If you’re into photography, there is a great course on Photoshop for Professional Photographers you should check out.
Open the image you want to edit in Photoshop by going to File>Open.
The tool we are going to use for this operation is located on your tool bar which is defaulted to the left side of your Photoshop screen. There are a bunch of little icons that represent different tool sets that Photoshop offers. For this project we’re looking for the eraser icon. The eraser icon, like most of them, has a subset of tools that appear in a fly-out menu if you right click the tool. So let’s start there.
Find the eraser, right click it and select background eraser tool. There is also a keyboard shortcut for activating this tool and it’s E. When you push E, you’ll probably get the eraser tool. Use the short cut SHIFT+E to rotate through the tools under the eraser.
After you’ve done this you should see a circle with a target, or cross hairs, in the center of it. This is your erasing tool. You can adjust the size of this brush by visiting the top left of your Photoshop screen. Look for the circle with a number below it inside of a box. Click there and you’ll see sliders that you can drag to the left or the right. Drag the slider to the right to make the brush bigger, and drag the slider to the left to make the brush smaller. You’ll also see some other options like angle, hardness and pressure – we don’t need to worry about these now. Next, look to the right of your brush size box on the horizontal toolbar. You should see a field that says contiguous, change this to find line. This tells the eraser tool to not just erase things in the shape of a circle, but to find the line of pixels surrounding the image you want to keep. It’s not perfect, but it’ll get you close to what you want. And finally, next to find line you should see a tolerance slider. We want our tolerance to be somewhere around 20%. This tells the brush to not tolerate colored pixels that aren’t similar to the sample. We’ll talk about that in a minute. I’m going to adjust my brush size to 40 for starters, set my tolerance limit and select find line.
Now, the technique behind this tool is complex but it makes your life easier. Don’t let that confuse you, I’ll explain.
Remember how we just set the tolerance to off? Here’s why. The brush you use to erase the background has a mechanism that only allows it to erase like colored pixels from the background. The color determination is the target center of the circle. For example, if I were to hold the brush over the sloth instead of the background and move my cursor around, the eraser would recognize the sloth as the object to be erased – and not the background colors. This means you can color outside of the lines as long as the target doesn’t touch an object you don’t want to disappear. The circle itself can brush over the object that stays – but the target can’t. Here’s an example:
If I were to drag the target of the brush over to the sloth, the sloth would begin to erase like the side of the sloth is being erased. The checkered background you see in the above photo is indicative of a transparent background. This means when you save the photo it will be all sloth and only sloth.
As you erase you’ll see that you need a lot of patience. The eraser tool takes its time getting rid of the background – especially in a picture with such a diversity of colors like this one. So to cut some time out, I’ve erased around the sloth head to the best of my ability with the current eraser settings.
Now, since the rest of the background I don’t care about and I don’t need to be careful about what gets erased, I can change the brush settings to have a higher tolerance (more accepting of the colors around the target area), change the limits back to contiguous and enlarge my brush. This will allow me to erase the background quicker without potentially erasing the sloth. Or, you can just skip straight to the eraser tool itself and do the same job just as quick. Like these tips? Learn more in the course Be a Photoshop Guru.
Okay, so let’s keep erasing and see how he looks.
So you’re looking at this picture thinking… that’s not a very good job. And you’re right, it’s not. The sloths hair was hard to work around and the background eraser didn’t totally erase all of his outline. So how do we fine tune this? We zoom in. Use the shortcut CTRL and the plus sign to zoom in, and CTRL and the minus sign to zoom back out. When you are zoomed in you can use a small brush to touch up around your object. I recommend using the regular eraser for this part. Learn how to use Photoshop actions to quickly edit photos in this article.
Save your photo! When you go to save your photo click on File>Save for web. You may notice some whitish blotches around where you used the background eraser tool. If so, just go back to the photo with the regular eraser and go over these spots. This will make your background 100% transparent on any background.
And :::drum roll::: here he is:
Now you can plop him into can photo you want, like this:
For more awesome tricks like this in Photoshop, check out the course on Photoshop Essentials.
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