What is layer mask in photoshop? How to use and apply layer mask in practice? Through this lesson we will explore and solve those questions together.
1. Layer mask in photoshop
Layer mask is also known as layer mask in photoshop . A Mask created to hide part or all of your layer. The thickness (coverage) of the layer mask depends on how dark the layer is. This means that the darker the layer mask is, the more the layer is covered.
Layer masks are used to crop images in Photoshop, and create mirror shadows. In addition, layer masks are also used for the purpose of removing or reducing part of the effect of effect layers (Adjustment Layers).
Operating principle
In Photoshop, layer masks operate on the principle of utilizing a separate layer, consisting of black and white colors, to selectively hide or reveal parts or the entirety of the original layer. This masking technique can be likened to wearing a physical mask. It means that the original layer, containing the image, remains unaffected and is merely covered by the layer mask.
To mask a portion of the original layer, you can simply fill the layer mask with black. Conversely, to reveal the original layer again, fill the layer mask with white. Additionally, if you wish to apply a partial blur effect to the original layer, filling the layer mask with gray can achieve that.
The key aspect to consider when working with layer masks is the intensity of the mask color, specifically referring to the black color applied to the layer mask. As the intensity of the mask color varies from white to black, ranging from 0 to 256, the degree of coverage changes accordingly. The darker an object appears in the mask, the more it is concealed, and vice versa.
How to use layer mask in photoshop
When working with layer masks in Photoshop, there are three primary methods for application: utilizing the brush tool to paint on the mask, employing gradients to fill the mask with color (specifically black), and directly filling the mask using selections. Despite the different tools used, the underlying mechanism remains the same. All three methods rely on the intensity of the mask color. The distinction lies in the tool chosen to generate this color. Let's explore each method in further detail.
Using a layer mask with the Brush tool
Step 1: Select the layer thumbnail to apply layer mask
. -> Click on the layer mask (at the bottom of the layer dialog). -> Now the thumbnail layer has an additional white layer next to it.
Step 2: Select the Brush Tool (B) 
-> Press the D key on the keyboard (Restore 2 color boxes to default
). -> Press the X key on the keyboard (fill it with black for the foreground color
)
Step 3: Right click on the desktop -> Adjust the size and hardness of the brush to suit
Step 4: Adjust the Opacity of the brush brush to get the right black intensity on the layer mask
Step 5: Lightly paint on the parts you need to cover (erase). -> now the object on your layer will be erased where the brush brush goes
Step 6: Get back or adjust the deleted object part. -> Press X again to (fill white for foreground color) -> Repeat step 3
Use selection to crop images
Step 1: Select the layer containing the object to be cropped
Step 2: Use the selection tools . -> Make a selection around the object to be cut
Step 3: Press Shift + f6 (to blur the cut). -> Click on the New layer mask tool .
Step 4: Delete more areas on the layer by: Create the same selection on the part to be removed -> Choose black for foreground color. -> Press Alt+Delete to remove the part to be deleted.
Step 5: Edit, or get back the deleted part.
Use gradients to color the mask
To utilize this particular method, the steps are similar to the previous two methods. However, this approach can be slightly more intricate, requiring a deeper understanding of gradients in Photoshop, along with additional practice and familiarity with layer masks. For a more comprehensive understanding of this technique, I recommend referring to an article specifically dedicated to creating shadows in Photoshop. This resource will provide detailed instructions and insights to further enhance your knowledge and skills in this area.
Notes on using layer masks
When using layer masks in Photoshop you need to note the following issues:
- Move the Layer Mask to another layer: To do this, click and hold the left mouse button on the layer mask. -> drag to the layer you want to apply layer mask.
- Copy Layer Mask: To copy the layer mask from one layer thumbnail to another layer thumbnail. From you key you hold Alt + click Layer Mask -> drag and drop on the Layer thumbnail you want to copy.
- Snooze layer mask: If you want to show full layer thumbnail you do Hold shift + click on layer mask
