Making double exposures with a film camera used to be tricky. To take a good multiple exposure, for example, your camera needed to have a special control that prevented the film from advancing while you captured each frame in the series. And you needed to underexpose each frame by just the right amount so that the final image wouldn't be overexposed from all those clicks of the shutter.

These days, creating a multiple exposure digitally is a snap. Let's see how.

Do It in the Camera

Just like in the days of film, it's possible to make a double exposure "in the camera," without involving your photo editing software--but only if your camera includes such a feature. Check your user guide for any multiple exposure mode options.

If you can make a multiple exposure with your camera, set it to the appropriate mode and snap away. Remember that since you'll be putting two or more exposures in the same image, you need to reduce the exposure of each picture you take. If you shoot two pictures, for example, a good starting place is to halve the exposure that each photo would normally get. To do that, set your camera's exposure compensation control to -1 for both shots.

Do It on the Computer

Few cameras have a multiple exposure mode, though, so you'll probably need to combine separate images in a photo editing program. There's no need to vary the exposure in this situation. Just take each photo the way you normally would, and transfer them to your PC. Then start up your favorite photo editor.

This technique makes use of layers, a feature that lets you "stack" images and vary their opacity. Most photo editors, like Adobe Photoshop Elements and Corel Paint Shop Pro, have this capability. I'll demonstrate with Photoshop Elements.

Stack Some Layers

Start Photoshop Elements and open the files that you want to use for your multiple exposure. They can be any images at all, as long as they all have the same pixel resolution. For this experiment, I'll use a sequence of photos I shot on my desk with some goofy toys: sample 1, sample 2, and sample 3.

You can use these photos or, if you prefer, combine a flower with a photo of a loved one, or a sequence of someone swinging a golf club. The possibilities are endless. Once you open all of your source photos in Photoshop Elements, you'll see thumbnails representing each one at the bottom of the window.

Now choose one of the photos and select its contents by pressing Ctrl-A. Choose Edit, Copy from the menu. Now select the next photo and choose Edit, Paste. This will paste the first photo into the second photo as a new layer. You'll be able to tell this has happened, because you'll see the two images in separate layers in the Layer Palette, on the right side of the screen, as the image to the right shows.

Finally, repeat the process for the remaining photo. Choose the remaining photo, press Ctrl-A, and choose Edit, Copy from the menu. Select the composite photo and choose Edit, Paste. You'll see all three images appear in the Layers Palette.

Tweak the Opacity

We're almost done. Select the top layer in the Layers Palette and vary the opacity slider until the layer underneath starts to show through. If you are creating a double exposure, this is pretty easy to do--set the opacity at 50 percent to start and then fine-tune it until it looks perfect. If you have three or more photos, though, it'll take some finessing to get a good result. In this example, I set the top layer to 50 percent and the middle layer to 70 percent.

Hot Pic of the Week

Get published, get famous! Each week, we select our favorite reader-submitted photo based on creativity, originality, and technique. Every month, the best of the weekly winners gets a prize valued at between $15 and $50.

Here's how to enter: Send us your photograph in JPEG format, at a resolution no higher than 640 by 480 pixels. Entries at higher resolutions will be immediately disqualified. If necessary, use an image editing program to reduce the file size of your image before e-mailing it to us. Include the title of your photo along with a short description and how you photographed it. Don't forget to send your name, e-mail address, and postal address. Before entering, please read the full description of the contest rules and regulations.

This week's Hot Pic: "Blue," by Todd Frantz, Rancho Cucamonga, California

Todd writes: "This little scene grabbed my attention because of the way the surface tension of the water bent to meet the flower, and the way the blue color of the flower flows into the blue water around it."

This Week's Runner-Up: "Pollination Pleasure," by Debra Ferris, Spring Hill, Tennessee

Debra writes: "I took this photo with a Canon 20D and a Lensbaby 2.0 attachment, using just natural lighting in the late afternoon. This bee was warning me that I was too close for his comfort. I was too close for my own comfort as well--I'm allergic to bees!"

See all the Hot Pic of the Week photos online.

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