User guide

Layers and Masks 47
To edit the active layer's mask:
Click the mask thumbnail, or check Edit Mask on the Layers menu.
In Edit Mask mode, you're normally viewing not the mask, but rather the effects of
changes "as if" you were making them on the layer below. Adding a Reveal All mask
can be a bit confusing, because there's initially no evidence the mask is there at all (i.e.
the layer appears exactly the same as it did before you added the mask)!
It's sometimes helpful to switch on the View Mask setting, which hides the layer and
lets you see only the mask, in all its grayscale glory. For example, a Reveal All mask
appears pure white in View Mask mode—the white represents a clear mask with no
effect on the underlying layer pixels' opacity. View Mask can also be useful in the
latter stages of working on a mask, to locate any small regions that may have escaped
your attention.
To view the active layer's mask:
Alt-click the mask preview thumbnail. Alt-click again to stop viewing the mask.
White or light portions of the mask reveal layer pixels (make them more opaque).
Black or dark portions hide layer pixels (making them more transparent).
You can disable the mask to see how the layer looks without the mask's effects. Note
that disabling the mask is not the same as cancelling Edit Mask mode—it only affects
your view of the layer, not which plane (i.e. mask or layer) you're working on.
To disable the active layer's mask:
Shift-click the mask preview thumbnail or right-click it and select
Disable Mask (or select from the Layers>Mask). (Shift-click again
or uncheck the menu item to enable masking again.)
When the mask is disabled, a red "X" appears across its thumbnail.
If you want to fine-tune a mask or layer's position independently of each
other it’s possible to unlink them. You may have noticed a small link button
between the layer and mask thumbnails on the Layers tab, i.e.