Saving and loading selections Creating a selection can be tedious, but fortu-nately, it can be saved either as an alpha channel or as a layer mask.. Display the Channels panel, then clic
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Creating a selection can be tedious, but
fortu-nately, it can be saved either as an alpha channel
or as a layer mask Once saved, a selection can be
loaded onto the document at any time, and can be
reshaped, if needed
To save a selection to an alpha channel:
1 Create a selection A
2 Display the Channels panel, then click the
Save Selection as Channel button on the
panel Press Ctrl-D/Cmd-D to deselect A new
alpha channel appears on the panel.B
➤ To reverse the masked and unmasked areas in
an alpha channel, click the alpha channel on the
Channels panel, then press Ctrl-I/Cmd-I
➤ To rename an alpha channel, double-click the
name, type a new one, then press Enter/Return
➤ To delete an alpha channel, right-click the listing
and choose Delete Channel
➤ Alpha channels can be saved with files in several
formats, such as Photo shop, JPEG 2000, TIFF,
and Photoshop PDF In the File > Save As dialog,
check Alpha Channels
To load an alpha channel as a selection:
On the Channels panel, do either of the
following:
Ctrl-click/Cmd-click the alpha channel
thumb-nail or listing Your selection will reappear in the
document window
Drag the channel name to the Load Channel as
Selection button at the bottom of the panel.
➤ To learn more about saving and loading alpha
channels, see Photoshop Help
A We created
a selection…
B …then clicked the Save Selection as Channel button on the Channels panel This alpha channel listing appeared.
RESHAPING AN ALPHA CHANNEL
➤ To reshape an alpha channel, click the channel, then with the Brush tool, paint with white to expand the selection area or with black to remove areas from it When you’re done, click the topmost channel
➤ If you prefer to display an alpha channel as a ruby-lith (a red tint), click the alpha channel, then click the visibility icon for the topmost channel To restore the normal display after reshaping the channel, hide the alpha channel by clicking its visibility icon (then click the topmost channel)
SAVING A SELECTION AS A MASK
If you save a selection as a layer mask, not only is it stored with the document, but you can also reshape it easily by editing the mask (see pages 169–170), and redisplay it as a selection at any time (see page 172)
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Refining selection edges
Use the improved Refine Edge dialog to apply
refinements, such as feathering, to your selections
Practical uses for this dialog are illustrated on pages
162–165 and 237
To refine the edges of a selection: ★
1 Create a selection With your selection tool still
chosen, click Refine Edge on the Options bar or
press Ctrl-Alt-R/Cmd-Option-R
2 Set the zoom level to 100% or 200% by pressing
Ctrl- +/Cmd- +
3. To control how the selection previews in the
doc-ument, choose from the View menu AYou can
also choose a view by pressing the letter shortcut
that’s listed on the menu, or cycle through them
by pressing F We’re partial to these views:
Overlay (V) to view the selection as a Quick Mask
(useful for viewing areas beyond the selection)
On Black (B) to view the selection against a black
background (useful if you’re going to copy the
selection to a dark background or if the
back-ground areas are light)
On White (W) to view the selection against a
white background (useful if you’re going to copy
the selection to a light background)
On Layers (L) to view the selection on top of the
layer immediately below it (useful for judging
the selection edge against an underlying layer, if
there is one)
4 Check Smart Radius to allow the Radius to adapt
to hard and soft edges in the imagery
If you want to widen the refinement area to
include pixels just outside the selection edge,
increase the Radius value (use the scrubby slider)
To view the current refinement area, check Show
Radius (J), then uncheck it before proceeding.
➤ At any time, press P to toggle between the
original selection and the refined one
5 In the Adjust Edge area, move any of the
follow-ing sliders, if desired:
To smooth out small bumps or jagged edges, raise
the Smooth value slightly.
To soften the transition between selected and
unselected pixels, raise the Feather value.
To heighten the contrast between pixels within
the refinement area to remove noise from a high
Radius value and produce a crisper selection
edge, increase the Contrast value.
To shrink the selection edge inward (to eliminate background pixels) or expand it outward from the
edge, adjust the Shift Edge value slightly.
6 In the Output area:
If you want to replace background pixels along the edges of the selection with colors from within
the selection, check Decontaminate Colors, then raise the Amount value.
Choose Output To: Selection to refine the
selec-tion without putting its contents on a new layer
Or to copy the selection contents to a new layer,
choose New Layer (no mask) or New Layer with Layer Mask (the shape of the selection appears
in a layer mask) If Decontaminate Colors is checked, only new layer options will be available
current settings become the new default values for the dialog
8 Click OK.
A To quickly switch among the View options in the Refine Edge dialog, press the letter shortcuts.
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REFINE A SELECTION EDGE AND CREATE A SILHOUETTE — ALL IN ONE DIALOG! ★
C We checked Smart Radius to allow the Radius to adapt to
the hard and soft edges in the image, and we increased the
Radius to 55 px* to include more of the fine feathers — this
also softened the edges.
D We increased the Contrast value to 8% to sharpen the border edges temporarily and create a more accurate selec-tion To judge our results against the solid-color layer, we chose On Layers from the View menu.
A We duplicated the
Background of a 300 ppi
photo, created a
solid-color layer below it, then
selected the parrot with
the Quick Selection tool.
B In the Refine Edge dialog, we chose On White (W) view and zoomed in to 100% With no refinement applied, the edges of the selection of the feathers and beak are imprecise.
*Use a lower Radius value for a low-resolution image.
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G These are our final Refine Edge settings To create a
silhouette using the current selection, we chose Output To:
New Layer with Layer Mask This option duplicated the
Background copy and turned our selection into a layer mask.
F We checked Decontaminate Colors and set the Amount value to 45% to remove any color fringe from the selection edge Decontamination results can be judged in On Layers,
On Black, or On White view.
E We increased the Shift Edge value (to +20%) to expand the
selection edge More of the soft feathers are now included,
but more of the original blue background color is, too.
H The new layer and layer mask appeared on the Layers panel
The final image
is shown above.
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Using the Refine Radius tool in the Refine Edge
dialog, along with the sliders, you can extend a
selection border into specific areas manually Here
we’ll use these features to refine a selection of
hair Although these steps won’t work magically
on every image, it’s a timesaver when they do
To refine a selection of hair via the Refine
Edge dialog: ★
1 Optional: Duplicate the Background, then create
a solid-color layer between the Background and
the duplicate image layer
2. In a photo that contains fine hair strands, use
the Quick Selection or Magic Wand tool to
create a selection.A
3 Click Refine Edge to open the Refine Edge
dialog Set all the sliders to zero and uncheck
Decontaminate Colors
4 Choose On White or On Black view (Or if you
created a solid-color layer below the duplicate
layer, choose On Layers view.) Check Smart
Radius and set the Radius value to 20–30 px B
5 Click the Refine Radius tool, and press X
to view the original image layer Press ] or [ to change the brush to a medium size, then drag over the fine hair strands Your brush work will display as green strokes (A–B, next page)
6. Press X to return to your View choice Raise
or lower the Radius value to better define the hair strands Also try increasing the Shift Edge
value slightly to reveal more strands (Keep the Contrast, Smooth, and Feather values at 0 so they don’t hinder the Refine Radius tool effect.)
7 Check Decontaminate Colors, then raise the Amount value until any background colors are
removed (C–D, next page)
8 Choose Output To: New Layer with Layer Mask, then click OK Now, wasn’t that easy?
A With a few clicks of the Magic Wand tool on this
300 ppi photo, we selected the sky, then chose Select >
Inverse.
B In the Refine Edge dialog, we zeroed out all the set-tings first To widen the refinement area to include more hair strands, we checked Smart Radius, then increased the Radius value The Smart Radius option produced a more accurate selection edge.
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B We pressed X to restore the preview
to On White view, then checked Show Radius to view the results of the expanded radius.
D To produce this result, we placed a white back-ground layer below the silhouetted image layer.
C For our final Refine Edge settings, we checked
Decontaminate Colors, set the Amount value to 82%, and
increased the Shift Edge value just enough to include more
fine hair strands without including any of the background.
A We clicked the Refine Radius tool, pressed X to preview the original image, then applied strokes over the fine hair strands and neck to control how much the radius extends locally
Our goal is to pick up more details along the edge.
➤ If you need to shrink the radius to remove details from the selection, apply strokes with the Erase Refinements tool