boasting the most contrast between
highlights and shadows. Click the Red
channel to view it in the image win-
dow, as in Figure 7-35. What you’re
seeing is called a luminance mask be-
cause you can use it just as it is to
select the light regions of the image.
- Ctrl-click (or �-click) the Red chan-
nel to load it as a selection outline.
That’s all it takes—your luminance
mask is ready to roll.
- Mask the effects of the smart filters. Re-
turn to the Layers panel. Turn on the fil-
ters by restoring the in front of Smart
Filters, and click the filter mask to make it
active. Ensure that the background color
is black Then press Ctrl+Backspace (or
�-Delete) to fill the selection with black.
- View the filter mask by itself. Press
Ctrl+D (�-D on the Mac) to deselect the
image. Next, Alt-click (or Option-click)
the filter mask thumbnail to view only the
mask. Pictured in Figure 7-36, this reverse
version of the Red channel is known as a
density mask because it reveals the dark-
est regions of the images, which in print
are the areas of highest ink density. The
upshot is that the effects of the smart fil-
ters are limited to the darkest areas of the
photograph.
Figure 7-36.
Alt-click (on the Mac, Option-click) the layer mask thumbnail
to return to the image. To compare the masked version of the
filters to the unmasked one, Shift-click the filter mask thumb-
nail, which turns it on or off. By masking away the filters in
the bright areas, we limit the sharpening and other effects to
the dark details, which represent the real edges in the image,
including the perimeter of the eyes, mouth, and nose. This is
digital sharpening at its most subtle, not to mention its best.
Figure 7-35.
Nondestructively Editing a Photo with Smart Filters 245
