How to Remove Objects from an Image's Background using Photoshop Elements 8

On of the most common tasks you'll perform using Photoshop is extracting a foreground image from the background. As with anything in Photoshop, there's usually multiple ways of achieving the same result. This excerpt from Barbra Brundage's Photoshop Elements 8 for Mac: The Missing Manual will introduce you to the Magic Extractor tool.

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Ever feel the urge to pluck an object out of your photo's background? For example, maybe you want to take an amazing shot you got of the moon and stick it in another photo. The traditional procedure is to make your selection, invert it, and then delete the rest of the image. But Elements streamlines this process with another "magic" tool—the Magic Extractor. It works much like the Quick Selection tool in that you just give Elements a few hints and let it do the rest. When the Magic Extractor's done, your selection is isolated in all its lonely glory, surrounded by transparency and ready for use on its own. Like the Quick Selection tool, this tool does a surprisingly good job—most of the time. To conduct your own experiments, download the practice photo (figurine.jpg.) from the Missing CD page at www.missingmanuals.com.

Tip: You may find it faster to use the Quick Selection tool, followed by inverting and deleting the background. If that doesn't work, it's time to try the Magic Extractor. The Magic Extractor has an elaborate dialog box with tools you won't find anywhere else in Elements. To see it, go to Image → Magic Extractor (see Figure 5-14). You see a full-screen dialog box, including a toolbox on the left side, instructions across the top, a preview of your image, and a set of controls at right. It looks complicated, but it's really just a bunch of easy-to-use options for tweaking things before Elements extracts your object. Here's how to use this timesaving tool:

Figure 5-14. Manually removing this figurine from its background would be a long process. With the Magic Extractor, these few marks are all the help Elements needs to make the selection for you.

• Go to Image → Magic Extractor or press Option-Shift-⌘-V.
  
  Your image appears in the preview area of the Magic Extractor window.
  
  Tip: The Magic Extractor sometimes has problems with large files. If you need to extract an object from a hefty image, you may get better results if you crop away any large, unnecessary areas first.
• If necessary, change the marker colors.
  
  On the right side of the window are two color squares. Usually, red is the Foreground brush (the one you use to mark what to keep) and blue is the Background brush (the one that tells Elements what to discard from your image). To make the brush tools easier to see, you can click the squares to call up the Color Picker and choose new colors.
• Use the Foreground brush to tell Elements what to extract.
  
  Make some marks on the object you want to keep. You can draw lines, as shown in Figure 5-14, but making dots on your object may work just as well. With practice, you'll soon get the hang of knowing what kind of marks you need for each object.
• Click the Background brush and tell Elements what to exclude.
  
  Similarly, make some marks in the areas you don't want Elements to include in your selection.
• Click the Preview button.
  
  The Preview area shows what Elements thinks you want to do, although it may take a few seconds to show up. If what you see isn't right, click Reset and start over.
• If necessary, use the various tools to help Elements adjust the boundaries of your selection.
  
  For example, if Elements left off an area you want, usually one click with the Foreground brush is enough to tell the program what to add. If there are spots missing within the selection, click the Fill Holes button. If you need to get a better view of your work, use the Zoom and Hand tools.
• Fine-tune the edges of your selection, if you wish.
  
  Add a feather, or smooth the edges of the selection with the Smoothing brush.
• When you like what you see, click OK.
  
  If you want to give up and try another method, click the Cancel button instead. Figure 5-15 shows what the Magic Extractor can do.

Figure 5-15. Just the few marks you saw in Figure 5-14 produce this perfectly extracted selection, all ready to move to another image.



Tip: Once you understand layers, you'll know that the Magic Extractor works only on the active layer of your photo. If you want to extract an object without wrecking the rest of your photo, make a duplicate layer and work on that new layer. The Magic Extractor gives you lots of ways to ensure that Elements makes a perfect selection. The toolbox contains a whole set of special tools just for the Extractor, as you can see in Figure 5-16. Each has its own keyboard shortcut to make it easy to switch tools while you work (given in parentheses after the tool's name in the list below). From top to bottom, you get:

Figure 5-16. The tools in the Magic Extractor's toolbox make it unbelievably easy to make complex selections and get smooth, professional-looking results when you extract objects.

• Foreground brush (Keyboard shortcut: B). Use this brush to mark what you want to include in your extracted object. You can change the brush color by choosing a different Foreground color in the square on the window's right side.
• Background brush (P). This brush tells Elements what to cut away from your selection. Like the Foreground brush, this brush has a color square on the window's right side where you can choose a different marker color.
• Point Eraser tool (E). If you mark something by mistake with the Foreground or Background brush, use this tool to erase the marks.
• Add to Selection tool (A). For adding to the selection you've already made.
• Remove from Selection tool (D). Whatever you paint over with this, Elements removes from your selection.
• Smoothing brush (J). Once you've previewed your selection, you can use this brush to even out any ragged edges. (Try the Touch Up commands on the right side of the window first and you may not need this brush.)
• Zoom tool (Z) and Hand tool (H). These are the same trusty standbys you use to adjust your view elsewhere in Elements.

Tip: Some of the fine-tuning tools, like the Smoothing brush, work better if you zoom in before using them.So you can see what you're doing, Elements gives you several ways to adjust the tools and your view of the image. These are on the right side of the window:

• Tool Options. You can choose different colors for the Foreground and Background brushes by clicking the color squares and using the Color Picker. You can also adjust the brush size, but that's hardly ever necessary, unless the brush is too big for the area you want to select.
• Preview. Choose whether to see just the selected area or your entire image. You can also choose what kind of background you want to see your selection against to get a clearer view. For example, you can choose None (the standard transparency grid), or a black, gray, or white matte, which puts in a temporary solid background to make it easier to check the edges of your selection. Mask is just like the black-and-white view of a layer mask. You can paint more of a mask or remove the mask to reveal a larger selection. (Remember that what's masked isn't selected.) Rubylith is just a fancy name for the red mask view as opposed to the black-and-white view you get with Mask.
• Touch Up. Once you've previewed your selection, you also get some helpful options for making sure the selection is perfect:
  • Feather. Enter the amount, in pixels, that you want Elements to feather the edge of your selection.
  • Fill Holes. If Elements left gaps in your selection, you may be able to fill them by clicking this button. This works only for holes that are completely surrounded by selected material, though. If the edges of your selection have bites out of them, use the Smoothing brush (Section 5.5) instead, or give the area an extra click with the Foreground brush.
  • Defringe. If your selection has a rim of contrasting pixels around it, this command can usually eliminate them. Figure 5-17 shows what a difference defringing can make. You can choose a number of pixels for Elements to consider when defringing, but the standard setting is usually fine. Actually, Elements is pretty good about making clean selections, so you probably won't need this button very often.

Tip: If the edges of your selection are ragged but not contrasting, or if defringing alone doesn't clean things up enough, try the Smoothing brush (Section 5.5). Just run it along the edge of your selection to polish it until it's smooth.Extracting objects used to be a time-consuming process, often involving expensive third-party plug-ins to make the job easier. But now the Magic Extractor is all you need in most situations.

Figure 5-17. Defringing is a big help in cleaning up the edges of your selections. It's so useful that Adobe makes it available even when you're not using the Extractor. You can always go to Layer → Defringe in Full Edit.

Top: Here's a close-up of the top of the mariner's hat. The black matte background makes the ragged edges stand out. If you place this image into another graphic, it'll look like you cut it out with dull nail scissors.

Bottom: The edges will blend into another image much more believably after you apply defringing. Here you can see how much softer the edges are after defringing. Now you can place the figurine into another file without getting the cut-out effect.