Fix Photoshop: Erasing a layer mask with background eraser tool showing error

Fix Photoshop: Erasing a layer mask with background eraser tool showing error Could not use the background eraser because the target channels do not cover the composite

I am trying to erase a mask layer with eraser tool. Got a message”Could not use the background eraser because the target channels do not cover the composite”

What possibly am I doing wrong?

Below are the reasons your eraser tool does not seem to work in Photoshop:

The Backgound Eraser tool can not work on a layer mask. The Background Eraser tool samples the colour at the centre of the brush, and deletes pixels of a similar colour as you drag around your image. You can use the normal Eraser tool on the layer mask which will give you an effect based on the gray scale value of the background color you have selected.

Table of Contents:

1. Part of your image is selected

You may have accidentally selected part of your image or forgot to deselect it. You may have used either the marquee tools, lasso tools, magic wand, or quick selection tools. You can only erase or edit pixels within the selected area. A very small part of your image may be selected that you can’t see the selection border.

How to Fix: Click Ctrl/cmd+D on your keyboard. This will deselect any part of your image that had been selected.

2. You have a duplicate image

You may have a duplicate layer or a background with the same colors or pixels as the part of the image you are trying to erase. If the layer above or below your current layer looks the same as your current one, you may be erasing your image but the other layers may be making you think you are not.

How to Fix: Use the eye (layer visibility) to hide other similar visible layers or your background and try erasing on your intended layer. You can delete any unwanted duplicate layers by right-clicking the layer, selecting delete, or using the trash icon on the layers panel.

3. You are working on a layer mask

If you have an active layer mask and it is selected then your eraser is working on the mask rather than your image/normal layer.

How to Fix: If you accidentally created a layer mask or don’t need it, you can delete it by right-clicking and deleting it. If you intend to work with the mask active, but want to erase your image select your image window.

You can also disable the mask or invert (ctrl/cmd+i) to reveal the masked area.

4. Default colors for layer mask are not set to black and white

If you intend to erase directly on your mask layer but the eraser tool is not erasing at 100% opacity, the problem is likely your default colors are not set to black and white.

How to Fix: Click D on your keyboard to change your default colors to black and white. You can use X to switch between the two colors as you erase your mask.

5. Your layer is locked

If you try to erase on a locked layer, Photoshop will give you an error dialog, stating that you can’t use the erase tool.

How to Fix: Unlock your selected layer by unchecking the lock icon in the layers panel.

6. Your selected brush and brush settings

The brush you are using may have been created with lower transparency or flow settings. This will give you a faulty brush even if the settings show it’s at 100% opacity. Your current settings may also be off.

How to fix: Use a different brush with your erase tool to see if it works. Check your opacity, flow, hardness, and size settings. You can see these settings at the top of your interface on the options bar or right-click on your canvas while the eraser tool is active to see the selected brush and its size and hardness settings.

7. The Pressure-sensitive pen settings

Your pen’s settings may be affecting Photoshop’s erase tools, especially on Wacom tablets.

How to Fix: If you are using a Wacom Intuos Pro, open the Desktop Center and click on Pen Settings. Under Pen, select Photoshop. Under “Tip Feel”, adjust the slider all the way to “soft”.

An alternative fix is to create a new erasing brush. Go to windows and click “brush settings” to open the panel. Click the “create new brush” icon. Uncheck the ‘Transfer’ box. Set your other settings as you’d prefer.

8. Photoshop settings were accidentally changed

You may have unknowingly changed some settings in Photoshop that have affected your eraser tool.

How to Fix: Rather than dig around to find the problematic setting, you can choose to Restore Photoshop to factory settings. Restore photoshop preferences by keeping Ctrl+alt+shift/Cmd+alt+shift while starting Photoshop.