With the new Masks panel, Photoshop CS4 has greatly improved the way essential masking techniques are implemented. Key controls are readily available and you no longer have to rely on convoluted workarounds to apply essential mask-editing modifications. All files are for personal use only. A new school had replaced it and only the entrance of the original building was left standing.
My nostalgic pilgrimage occurred in the late afternoon, shortly before sunset and the edifice was backlit. These challenging lighting conditions meant that in order to get a decent exposure of the wonderful educational graphics over the window, the late afternoon sky would be blown out.
The new sky has already been placed in the practice file as a separate layer. Now click on the Color Range button near the bottom of the Masks panel to bring up the Color Range dialog. This opens the Feather Selection dialog box where we can enter a Feather Radius value, in pixels, to specify the amount of feathering we want to apply to the selection edges. Problem is, how we know what value to enter? In my case, what's the exact feathering value I need here to create an ideal transition between the selection and the white background behind it?
The correct answer is, I have no idea. All I can do is guess at a value. Since the Feather Selection dialog box gives me no other choice, I'll play along and enter a value of 30 pixels, which is nothing more than a guess:. I'll click OK to close out of the Feather Selection dialog box, and now if we look again at my elliptical selection in the document window, we see that it looks In truth, the selection edges are now softer, but Photoshop's standard "marching ants" selection outline has no way of indicating that the edge is feathered.
It still looks like a solid, hard edge. I wish I could be of more help. Photoshop shouldn't feel too bad, though, because it actually can be of more help.
In fact, it can give us a full preview of what our feathered edges look like. It just can't do it using the Feather command and the standard selection outline. What we need, then, is another way - a better way - to feather selection edges, and that way is with Photoshop's Quick Mask mode.
Then, I'll click on the Quick Mask icon at the very bottom of the Tools panel. To switch between it and the Magic Wand, press Shift-W. To use this wonderfully friendly tool, click anywhere in the area you want to select or drag the brush cursor across it, as shown in Figure When you do that, Photoshop thinks for a second and then creates a selection based on the color of the pixels you brushed across.
Chapter 12 covers brushes in detail. If the color of the objects you want to select differs greatly from the color of their background, like these chili peppers, take the Quick Selection tool for a spin. With this tool activated, you can either single-click the area you want to select or drag your cursor circled across the area as if you were painting.
As you learned earlier in the chapter, this mode lets you add to an existing selection or make multiple selections. When you activate the Quick Selection tool, the Options bar offers three modes see Figure , just like the marquee tools Selecting by Shape :. New selection. Add to selection. Now Photoshop adds any additional brushstrokes or clicked areas to your current selection. The old selection disappears as soon as you start to make a new one.
Subtract from selection. Adding to a selection can make Photoshop select more than you really want it to. Brush Size. Use a larger brush to select big areas and a smaller brush to select small or hard-to-reach areas.
In other versions of the program, you can decrease your brush size by pressing the left bracket key [ ; increase it by pressing the right bracket key ]. Sample All Layers. The box below has tips for using this feature. If you have an older computer, you may have better luck using the Refine Edge dialog box Using the Tools Together to create selections with smooth edges.
That way, you get the benefit of using Auto-Enhance and keep your computer running quickly until the last possible moment. Use the Magic Wand to select solid-colored backgrounds or large bodies of similar color, like a cloudless sky, with just a couple of clicks. The Quick Selection tool, in contrast, is better at selecting objects rather than big swaths of color.
When you click once with the Magic Wand in the area you want to select, Photoshop magically hence the name selects all the pixels on the currently selected layer that are both similar in color and touching one another see Expanding your selection to learn how to tweak this behavior.
If the color in the area you want to select varies a bit, Photoshop may not select all of it. With its tolerance set to 32, the Magic Wand did a good job of selecting the sky behind downtown Dallas. When you activate the Magic Wand, the Options bar lets you adjust the following settings:. If you increase this setting, Photoshop gets less picky in other words, more tolerant and selects every pixel that could possibly be described as similar to the one you originally clicked.
If you decrease this setting, Photoshop gets pickier and selects only pixels that closely match the original. Out of the box, the tolerance is set to 32 though it can go all the way up to If you set it to 0, Photoshop selects only pixels that exactly match the one you clicked; if you set it to , the program selects every color in the image.
You have to click the area again to make Photoshop recalculate its selection. Leave this setting turned on to make Photoshop soften the edges of your selection ever so slightly.
If you want a super-crisp edge, turn it off. If you turn this setting off, Photoshop goes hog wild and selects all similar-colored pixels no matter where they are. Sample all layers. If your document has multiple layers and you leave this checkbox turned off, Photoshop examines only pixels on the active layer and ignores the pixels on other layers.
Did you know you can change the way the Magic Wand calculates which pixels to select? You can read about the Eyedropper tool—see Appendix E , online at www. Over in the Tools panel, select the Eyedropper tool its icon, not surprisingly, looks like an eyedropper; it lives beneath the Crop tool.
When you do that, a Sample Size pop-up menu containing a slew of settings appears in the Options bar. From the factory, the Sample Size menu is set to Point Sample, which makes the Magic Wand look only at the color of the pixel you clicked when determining its selection.
After you make your selection, simply activate the Magic Wand and then click somewhere in your image to see the effect of the new setting.
Sometimes the Magic Wand makes a nearly perfect selection, leaving you with precious few pixels to add to it. You could Shift-click the elusive areas to add them to your selection, but the Select menu has a couple of options that can quickly expand the selection for you:. You also can run these commands more than once to get the selection you want. After clicking once with the Magic Wand with a tolerance of 32 , you still need to select a bit more of the red left.
Since the red pixels are all touching each other, you can use the Grow command to expand your selection. Bottom: If you want to select the red in these playing cards what a poker hand! In this case, click once with the Magic Wand to select one of the red areas left and then use the Similar command to grab the rest of them right.
After grabbing the sky, you can inverse flip-flop your selection to select the buildings instead. The lesson here is that it pays to spend a few moments studying the area you want to select, as well as the area around it. If the color of the surrounding area is uniform, reach for one of the tools described in this section and then inverse your selection. It can save you tons of time! The Magic Wand tends to select whole pixels, whereas Color Range is more fine-tuned and tends to select more partial pixels than whole ones.
This fine-tuning lets Color Range produce selections with smoother edges less blocky and jagged than the ones you get with the Magic Wand and get in more tightly around areas with lots of details. If you already have a selection, Color Range looks only at the pixels within the selected area, which is helpful if you want to isolate a certain area.
Use the Select pop-up menu at the top of the Color Range dialog box to tell Photoshop which colors to include in your selection. The menu is automatically set to Sampled Colors, which lets you mouse over to your image your cursor turns into a tiny eyedropper; see Figure and click the color you want to select. The Color Range command is handy when you need to select an area with a lot of details, like the red and blue petals of these flowers.
You can tweak the area Color Range selects by adjusting its Fuzziness setting. Its factory setting is 40, but you can change this number to anything between 0 and If you increase it, Photoshop includes more colors and makes larger selections. If you lower it, Photoshop creates a smaller selection because it gets pickier about matching colors. Use the eyedroppers on the right side of the dialog box to add or subtract colors from your selection.
Use the plain eyedropper to make your initial selection. It sometimes helps to keep the Fuzziness setting fairly low around 50 or so while you click repeatedly with the eyedropper. The Selection Preview pop-up menu at the bottom of the dialog box lets you display a selection preview on the image itself.
In other words, instead of using the dinky preview in the dialog box, you can see your proposed selection right on your image. The two erasers covered here let you erase parts of your image based on the color you touch with your cursor. All you have to do is think ahead and create a duplicate layer before you start erasing, as this section explains. Say you have an image with a decent amount of contrast between the item you want to keep and its background like a dead tree against the sky.
In that case, Photoshop has a couple of eraser tools that can help you erase the sky super fast see Figure Sure, you could use the Magic Wand or Quick Selection tool to select the sky and then delete or mask it Layer Masks: Digital Masking Tape , but using the Background Eraser lets you erase more carefully around the edges and then add a layer mask to hide the rest of it.
Just click and hold the Eraser tool until the little pop-up menu appears. Pick an eraser based on how you want to use it: You drag to erase with the Background Eraser as if you were painting, which is great for getting around the edges of an object , whereas you simply click with the Magic Eraser.
The keyboard shortcut for activating the Eraser tool is the E key. To switch among the various eraser tools, press Shift-E repeatedly. When you activate the Background Eraser by choosing it from the Tools panel, your cursor turns into a circle with a tiny crosshair in its center.
This crosshair controls which pixels Photoshop deletes, so be extra careful and let it touch only the pixels you want to erase. Up in the Options bar, you can tweak the following settings for this tool see Figure :. Brush Preset Picker. This is where you choose the shape and size of your brush. For best results, stick with a soft-edge brush. Just click the down-pointing triangle next to the Brush Preset Picker to grab one. Made up of three buttons whose icons all include eyedroppers, this setting controls how often Photoshop looks at the color the crosshair is touching to decide what to erase.
If your background has a lot of color variations, leave this set to Continuous so Photoshop keeps a constant watch on whatwhich color pixels the crosshair is touching. To choose the color, click the background color chip at the bottom of your Tools panel Colors , mouse over to your image, and then click an area whose color is similar to the color you want to erase.
If you want to erase similar-colored pixels elsewhere in your image for example, the background behind a really thick tree or a bunch of flowers , change the setting to Discontiguous. Protect Foreground Color. If the area you want to keep is a different color in different parts of your image, you can turn this setting off or Option-click Alt-click to resample the foreground area.
If you want to practice erasing this background, you can download DeadTree. Even though the Background Eraser is destructive because it erases pixels, you can use it in a nondestructive way by remembering to duplicate the soon-to-be-erased layer first.
Then load the erased layer as a selection and use it as a layer mask on the original layer. As you can see here, Photoshop pays attention only to the color you touch with the crosshair in the center of the brush. Grab the Background Eraser tool and paint away the background.
The Background Eraser tool is part of the same toolset as the Eraser tool see Figure If you need to, you can increase and decrease your brush size by pressing the left and right bracket keys on your keyboard, respectively. If the tool is erasing too much or too little of your image, tweak the Tolerance setting in the Options bar also shown in Figure Hold your mouse button to erase a bit of the area around the object, let go of the button, click it again to erase a little more, and so on.
Once you get a clean outline around the object, switch to the regular Eraser tool see Appendix E , online at www. After you erase the hard part—the area around the edges—with the Background Eraser, you can use the regular Eraser tool, set to a large brush, to get rid of the remaining background quickly. You can also use the Lasso tool to select the remaining areas and then press the Delete key Backspace on a PC to get rid of them.
Load the erased layer as a selection and turn off its visibility. Select the original layer, turn on its visibility, and then put a layer mask over it. In the Layers panel, click once to select the original layer the unlocked Background and then click the area to the left of its thumbnail to make it visible again.
While you have marching ants running around the newly erased area, add a layer mask Adding Layer Masks to the original layer by clicking the circle-within-a-square icon at the bottom of the Layers panel. To edit the mask, click its layer thumbnail over in the Layers panel. Then press B to grab the Brush tool and set your foreground color chip to black Colors. If you need to reveal more of the tree, set your foreground color chip to white, and then paint the area you want to reveal.
How cool is that? Be careful to surround the area you want to keep completely with the Edge Highlighter. Next, switch to the Fill tool at the top left of the dialog box it looks like a paint bucket and click within the area you want to keep it will turn purple. This filter is destructive, meaning that Photoshop gets rid of the deleted areas for good. When the filter has finished processing, load the duplicate layer as a selection and then add a layer mask to the original layer just like you did with the Background Eraser on The Background and Magic Erasers.
That way, you can edit the mask if you need to clean up any of the edges. Or, if you own Photoshop CS3, you can drag and drop it from the older version of the program into the new one. You should see the Extract filter in the Filter menu from now on.
This tool works just like the Background Eraser except that, instead of a brush cursor that you paint with, you get a cursor that looks like a cross between the Eraser tool and the Magic Wand. The Anti-alias checkbox works the same way as in the other selection tools described in this chapter: Turning it on makes Photoshop slightly soften the edges of your selection.
If you want to erase pixels that touch each other, leave this checkbox turned on. If you want to erase similar- colored pixels no matter where they are in your image, turn this checkbox off. Using a selection tool, make your selection. HINT: Leave a little room along the edges for the feathering action.
It feathers on both sides of the selection border. From the Select menu, select Modify » Feathe r The Feather Selection dialog box appears. In the Feather Radius text box, type your desired feather pixel value.
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