Photoshop CS Timesaving Techniques For Dummies [Electronic resources] نسخه متنی

Layer Masks 101: How They Work

I’m sure that you’ve worked with layer opacity by now. For instance, if you move the Opacity slider on the Layers palette down from 100%, the layer starts to become translucent. Lower the Opacity slider all the way to 0%, and the layer disappears altogether.

But, how to you hide one part of the layer and leave another part of the same layer visible? Do it with layer masks.

For my demonstration today, the friendly looking alien in Figure 49-1 has volunteered to help me. (Cute, isn’t he? I especially like the jaunty hat over one eye.)

Figure 49-1: This happy looking fellow is going to help with the layer mask demonstration.

Here’s the layer mask demonstration:

In the Layers palette, click Create New Layer and fill the layer with white.

A quick way to do this is to press D, and then press X, and then press Alt+Backspace/Option+Backspace. A new layer appears above the layer containing the alien, so the alien disappears, and all you can see is the white layer. (I omit the figure here because I’m sure that you can imagine a white layer.)





In the Layers palette, select the layer that you want to add the layer mask to.

For this example, select the white layer.





Click the Add Layer Mask button at the bottom of the Layers palette.

A layer mask appears linked to the layer, as shown in Figure 49-2.




Figure 49-2: The layer mask appears linked to the layer.








Tip

A layer mask can be added to any layer except the Background layer.








Remember

The tiny link icon that appears to the left of the layer mask thumbnail indicates that if you move or transform the layer, the layer mask will be transformed at the same time.






Select black as the Foreground color.

A quick way to do this is to press D.





Select the Brush tool from the Toolbox and select a simple brush tip from the Brush Preset picker on the Options bar.

For this example, I’m using a brush tip with a 50 pixel diameter and a 100% Hardness setting.





In the Layers palette, click the layer mask to select it.






Stroke with the Brush in the image window.

As you paint with black on the layer mask, the areas that you cover hide the white layer that the layer mask is attached to and reveal the alien below, as shown in Figure 49-3.




Figure 49-3: Painting with black reveals the layer below. Notice where the black area is on the layer mask and the corresponding area in the image window.

Following the preceding steps, you discover that

White on a layer mask leaves the attached layer visible, hiding the layer underneath.

Black on a layer mask hides the attached layer, revealing the layer underneath.

But, what about gray? Painting on a layer mask with gray is like using the Opacity slider on the Layer palette. Gray makes a layer mask translucent. You can vary the opacity by using lighter or darker grays. Lighter grays leave the layer mask more opaque, and darker grays make the layer mask more transparent, as shown in Figure 49-4.

Figure 49-4: Painting with different shades of gray makes the layer mask more or less transparent.