How to use masking in Photoshop?

Detailed tutorial to show how to use masking in Photoshop with some advanced and useful things about Layer Masks.

Hi, in this tutorial I am going to show you how masking works in Photoshop. I will also cover many additional tricks regarding masking that many Photoshop users don’t know. Now those who are new to Photoshop masking, it’s very important for them to understand what actually masking is. Masking is a technique in which a layer works as a mask for another layer. You can also use the eraser tool to get the same effect but Masking is a highly recommended technique due to its non-destructive working which lacks in Eraser tool.

Ok, before going further into masking process, let’s understand the working of masking. Masking process uses Layer masks. Layer masks work according to the black and white values. More black means more transparency and vice versa. (See image)

masking in photoshop

In the given image, we have two spots on the layer mask to demonstrate the effect of amount of Black and White values. First has 100% Black, second one has 50% of Black 50% of White (Grey).

In 100 % Black, the layer become 100% transparent and reveals the layer underneath it.

In 50% of Black and white, the layer become 50% transparent and 50% opaque (due to the presence of white) and the layer behind it will 50% reveal.

Note: If the area is 100 % White then the layer will remain 100% Opaque.


masking in photoshop

Here, I have two layers in the document – one have an elephant image (the uppermost image) and other have a Leopard image on it.

In order to use masking, we have to add layer mask to the upper most layer in the Layers panel. So go ahead select the top most layer and click on Add layer mask icon present at the bottom of the Layers panel.


masking in photoshop

Now, Select Layer mask by clicking on it then select Brush tool (B) from the toolbar. Choose Black as your foreground color and start painting with your mouse and notice the layer behind the current layer starts revealing. Before you start masking, please make sure that the Layer mask is selected.

Tip: If you masked the wrong area by mistake then set your foreground color as White and paint over the area you want to recover.

Step 3

masking in photoshop

But it’s not necessary to use Black color in every case. You can also use Grey color so that it will preserve the layer for being completely transparent. It depends on the amount of White color present in Grey. Using Grey instead of Black gives quite satisfactory results. But if you are using Black then you can adjust the Opacity and Flow parameters of the Brush tool. By doing this you can achieve some nice and satisfactory results. (I am using Black color with a soft round brush with 15% of Opacity).

Step 4

masking in photoshop

You can Enable/Disable the layer mask by Shift + clicking on it or by right click on it > Disable/Enable Layer mask.

Step 5

masking in photoshop

To display the Black and White mask view in the canvas, just Alt + click on the layer mask. Notice that this view only displays the Black and White mask information but not the images you are working on. It’s just like a bigger view of the layer mask thumbnail.

Note: Sometimes you may find the Black and White mask view a bit difficult to use as it displays mask only but not the images so it’s hard for us to know which part of the image is being masking.

Step 6

masking in photoshop

Beside Black and White mask view, you can also work with the colored mask display in which masked area is indicated by a color you specify. To enable or disable this just press Shift + Alt + click on the Layer mask. To change the color of the mask, just right click on the layer mask then click Layer Mask Options… it will brings up the Layer Mask Display Options dialog. From this dialog you can change the color of the mask and adjust the opacity of the color.

Note: Unlike Black and White mask view, the colored mask view also displays the images you are working on.

Step 7

masking in photoshop

By right clicking the layer mask, you can also access some options that will help you dealing with selections while working with layer masks.

  • Add Layer Mask To Selection (Ctrl + Shift) + click on layer mask
    Adds the layer mask (white portion) to selection.
  • Subtract Layer Mask From Selection (Ctrl + Alt) + click on layer mask
    Subtracts the layer mask from selection.
  • Intersect Layer Mask With Selection (Ctrl + Shift + Alt) + click on layer mask
    Intersects the layer mask with selection.

You can also delete the layer mask by right clicking the layer mask > Delete Layer Mask.

You can also apply the layer mask permanently to your layer by right clicking the layer mask > Apply Layer Mask. (I do not recommend this step as it deletes the layer mask and we’ll not be able to readjust the areas that we masked previously)

Comparing Eraser tool and Layer Mask

As I said that we can get the same results by making use of Eraser Tool, so why don’t we use Eraser? Here is the quick comparison between Eraser tool and the layer mask that clears the fact why we use layer mask and not the Eraser tool.

masking in photoshop

Eraser tool erases the pixels of the image so that the layer behind that image starts to reveal. But what it actually does, it directly erases the pixel of our image and that means it destroys the image. Disadvantage of using Eraser tool is that the deleted area may not be recoverable if erase action ran out of the history Panel states. On the other hand, layer mask treats images in non destructive way and can be edited or deleted anytime which is a big advantage of layer mask over Eraser tool.

Now, you should have basic knowledge of how to use masking in Photoshop and how it works within Photoshop. Go ahead, try it out and create some cool things using masking and let me know if you have any problem regarding this tutorial through your comments and emails. Thanks.