Layer Mask is an ideal way to make your Action suitable specifically for your photo.

They allow you to have the action’s effect appear on part of the photo, but not the entire image.
Using them is also essential for most of the retouch actions in HELLO WORLD action set
(Baby Skin Smoothers, for example) which requires you to paint on the layer masks to make the effect appear where you need it.

This is your layer masks – the black or white box next to your layer thumbnails.

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First you need to know that white reveals and black conceals.

If the layer mask is white, it means the layer effects are visible.

To hide the layer (or the group of layers) effect from the part of the image:

1. Make sure that the layer mask is selected (if no, just click on it once).

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2. Select a black brush.
3. Paint over those areas of the image from which you want to remove the effect of the layer.
4. The Layer Mask will look white with black areas.

 

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If the layer mask is black, it means the layer effects are hidden.
This is important to remember when using actions such as Baby Skin Retouch,
because when the action finishes running you won’t see any difference until you start revealing the Action effect.

To reveal the layer (or the group of layers) effect:

1. Make sure that the layer mask is selected (if no, just click on it once).

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2. Select a white brush.
3. Paint over the part of the image where you want to show the effect of the layer.
4. The Layer Mask will look black with white areas.

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