Digital Focus: Improve the Background in Your Photos

Feature: Punch Up the Sky

Digital photography and digital trickery go hand in hand. Even if you just change the color balance or contrast in an image, you're tweaking reality. And sometimes more aggressive action is called for. Take the sky, for instance. I bet that if you browse through your photos, you'll find that most of your outdoor shots lack a certain punch--the sky is washed out, cloudless, or just a little boring.

There's a good reason for that. When you compose a photograph, you usually concentrate on the primary subject and pay little heed to the surroundings. Since the sky is a lot brighter than your subject, the camera over-exposes it--your skies end up looking a little bleached. By adding some snap back into your skies, you can improve so-so photos dramatically.

Multiply Your Sky

The easiest way to fix a bleached sky is to "multiply" it. We're going to open a photo, select the sky, and copy it the clipboard. Then we'll paste copies of the sky back into the image, using a seldom used tool to "multiply" the colors in each layer of sky to produce deeper, darker hues. This technique is ideal if there's even a little blue peeking through your sky, because it's so easy to do.

For starters, find a picture with a pale, weak sky and open it in an image editor like Paint Shop Pro. Here's one I found--skies rarely come more anemic than this.

Meet the Wand

Now we'll use the Magic Wand tool to select the sky in the photo. The Magic Wand is one of my favorite selection tools because it grabs parts of a photo that share similar colors.

On my default installation of Paint Shop Pro 7.0, the Magic Wand is the eighth tool down on the vertical tool bar (it resembles a wand with a glowing end). Click the Magic Wand to select it, then right-click to invoke an options menu. Select Tool Options. If the Tool Options--Magic Wand dialog box doesn't seem to be open, it's likely nested near the edge of the photo; hover your mouse pointer over it and it will pop open. Setting the Tolerance value determines how sensitive the wand is to color changes. Set it to 10, for instance, and it will select only a small region in the immediate vicinity of where you clicked; use a tolerance of 30 and each click will select a much larger area with broader color changes. For our purposes, set the tolerance to about 25--you can experiment and change this value if you want to. Close the dialog box.

Now we're ready to select the sky. Click the middle of the sky: You should see selection marks appear around a big blotch of sky. But you probably didn't get the whole sky. We'll use the Shift key to add multiple Magic Wand selections together. Look for parts of the sky that aren't selected and click on them, being sure to hold down the Shift key with each click. If the skyline is irregular, you may want to zoom in (click View and choose your zoom level) to see what you're doing.

Copy and Paste

Done? Good. Make sure that you've selected the entire sky--you can zoom in and pan around the image to double-check. Copy the selected sky to the clipboard by pressing Ctrl-C or selecting Edit, Copy.

Now choose Edit, Paste and add the sky into the picture as a new layer. In Paint Shop Pro you'd select Edit, Paste, As New Layer. You can tell that there are two copies of the sky in the picture because you can actually grab the sky layer that's in the foreground and drag it around. Position the new sky so that it lines up perfectly with the original sky underneath. This part can be rather tricky. It may help to zoom in further and make sure you choose one very detailed area to line up.

Be Clever and Multiply

Now for the magic trick that makes all this effort worthwhile: the multiply effect. In Paint Shop Pro, choose Layers, Properties from the menu and you'll see the Layer Properties dialog box. Set the Blend mode to Multiply. When you click OK, you should see the colors in your sky immediately deepen. (If you're using Adobe PhotoShop, go to Layer, Layer Style, Blending Options.)

Not enough change to suit you? Here's where your artistic judgment comes in. Since the sky is already copied into your clipboard, you can continue to paste new layers into your image until you get the deep and colorful effect you're looking for. My image looks much better after multiplying four layers of sky.

Remember, though: Every time you paste in a new layer, be sure to set the blend for that new layer to Multiply. You can use this technique to transform an anemic, pale blue sky into an angry, stormy scene in minutes.

Or Just Replace It

That's not the only way to punch up a lame sky. Next week I'll show you how to steal the a sky from another photo.