Background Eraser Tool

Background Eraser Tool

Learn how to use the Background Eraser Tool in Photoshop.

When to use

The Background Eraser Tool can be useful when you want to remove a specific color or group of colors from an image. 

Instructions

Getting Started with the Background Eraser Tool

• Begin by clicking and holding on the Eraser Tool to reveal the other tools nested inside.
• From here we will select the Background Eraser Tool.
• You can also access this tool by pressing Shift+E on the keyboard until you have the appropriate tool selected.
• After selecting the tool, create a copy of your Background layer to work from before turning off the visibility of the original.

Sampling Options

• Along the top toolbar you have several options that will determine how the tool is being used. 
• The first group of options refer to the sampling, and the first is called 'Continuious' which will continue sampling similar colors of that are next to each other.
• The next sampling option is called 'Once' which will sample the initial color where you click the mouse and Photoshop will continue to remove this color from wherever you erase.
• The next sampling option is 'Background Swatch' and this will select a specific color to remove from the image without affecting the others. 

Limit Options

• After the Sampling options we have a section called 'Limits' which will help us determine which type of pixels we want to erase.
• The first option called 'Discontiguous' means pixels that are not touching or next to each other.
• The second option called 'Contiguious' means pixels that are connected or touching.
• The last option called 'Find Edges' means that Photoshop will do its best to determine where the edges are in an image to erase more precisely. 

Tolerance

• After the Sampling and Limit options, we have something called 'Tolerance'.
• This refers to the intensity or strength of the overall Background Eraser.
• For best results, leave this somewhere between 30-50%. 

Removing a Sky with the Background Eraser Tool

• Start by choosing the first Sampling option - Continuous.
• Choose the 'Contiguious' option for the Limits.
• Begin brushing over the background of the photo and you will see that we are removing more than just the background. 
• To fix this, we need to find the right Sampling and Limit type to get a more accurate sampling of the background colors.
• Use the Undo command (Command/Ctrl+Z) to go back to the full image before we begin erasing.
• Change the Sampling to 'Once' and leave the Limits set to 'Contiguious'. 
• Click the mouse somewhere in the sky of the photo and continue brushing over the rest of the sky in the image to remove it.
• To select smaller areas of the sky, you can also reduce the size of the eraser using the left bracket key, or scale it up for larger areas with the right bracket key.
• In order to check how much of the sky has been removed, you can add a Solid Color Adjustment Layer and place it below the layer.

Removing Semi-Transparent Pixels with the Background Eraser Tool

• Start by opening the photo of the string lights and light bulb and duplicating the Background layer before turning the visibility of the original layer off. 
• Using the Background Eraser Tool with the same settings, begin erasing the glass on the inside of the light bulb.
• Continue to erase around the edges of the trees and the light post to remove the background.
• Add a solid color below the duplicate layer to see how the results are looking.
• Change the Sampling to 'Background Swatch' and then change the Limits to 'Find Edges' before brushing over the power lines to remove the background behind them.
• This should also work nicely for going around the edges of the buildings. 
• For any larger areas of the background, feel free to use the regular Eraser Tool to remove the background. 

Hints & tips

• When using the Background Eraser Tool, pay attention to where the small '+' icon appears in the center of the circle as this is where the sampling will happen.
• Experiment with the different Sampling options and the Limits to see which works best for removing areas of color.
• The Background Eraser Tool is particularly useful for isolating glass, feathers, nets, curtains, or anything else with semi-transparent pixels.