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ptg 160 Chapter 9 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. 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 les 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. is 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). ptg Selections & Masks 161 Refining selection edges Use the improved Rene Edge dialog to apply renements, 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. A You 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 renement area to include pixels just outside the selection edge, increase the Radius value (use the scrubby slider). To view the current renement area, check Show Radius (J), then uncheck it before proceeding. ➤ At any time, press P to toggle between the original selection and the rened 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 renement 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 rene 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. 7. Optional: Check Remember Settings to have the current settings become the new default values for the dialog. 8. Click OK. A To quickly switch among the View options in the Rene Edge dialog, press the letter shortcuts. ptg 162 Chapter 9 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 ne 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 Rene Edge dialog, we chose On White (W) view and zoomed in to 100%. With no renement applied, the edges of the selection of the feathers and beak are imprecise. *Use a lower Radius value for a low-resolution image. ptg Selections & Masks 163 G  e s e a r e o u r  n a l R e  n e E d g e s e t t i n g s . T o c r e a t e a silhouette using the current selection, we chose Output To: New Layer with Layer Mask. is 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  e n e w l a y e r and layer mask appeared on the Layers panel.  e  n a l i m a g e is shown above. ptg 164 Chapter 9 Using the Rene Radius tool in the Rene Edge dialog, along with the sliders, you can extend a selection border into specic areas manually. Here we’ll use these features to rene 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 ne hair strands, use the Quick Selection or Magic Wand tool to create a selection. A 3. Click Refine Edge to open the Rene 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 ne 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 dene 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 Rene Radius tool eect.) 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 Rene Edge dialog, we zeroed out all the set- tings rst. To widen the renement area to include more hair strands, we checked Smart Radius, then increased the Radius value. e Smart Radius option produced a more accurate selection edge. ptg Selections & Masks 165 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 nal Rene Edge settings, we checked Decontaminate Colors, set the Amount value to 82%, and increased the Shift Edge value just enough to include more ne hair strands without including any of the background. A We clicked the Rene Radius tool, pressed X to preview the original image, then applied strokes over the ne 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 Renements tool. . channels can be saved with les 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. 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. 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

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