Shooting Infrared With Your Digital Camera

Infrared light is at the lower end of the spectrum, just below the red in the ROY G BIV color spread that you no doubt learned in high school. Humans can't see infrared, and photographs exposed to infrared light look dramatically different, as if you're seeing the world through the eyes of a bat or one of those aliens in "Predator." Trees and plants can glow a bright, luminous white, while the sky often looks much more turbulent. Indeed, infrared photography is often like peeking into another world. Best of all, for our purposes, you never really know what you'll get when you press the shutter release. It's like a photographic grab bag.

Infrared photography has been around for quite a long time. Photographers have experimented with infrared film for years, but shooting in infrared was tricky for a whole bunch of technical reasons. If you want to experiment with infrared, digital is a much easier way to go.

Before you can begin, you need to find out if your digital camera is capable of seeing in infrared. Not all cameras can; some include a "hot mirror," which is designed to block infrared light.
Go grab an infrared remote control, like the one that operates your television or stereo. Point it toward your camera's lens and look at the camera's LCD. When you press a button on the remote, does your camera's display show a red light at the end of the remote? If it does, the camera is sensitive to infrared and you're ready to go. If you don't see the remote's light, then your camera has a hot mirror and you'll have to file away this information away until you come by a camera that can handle infrared light.

Go Invisible

As you have probably guessed, you need some way to prevent visible light from entering the camera lens when you shoot in infrared. What you need is a filter. Infrared filters are designed to block most or all of the visible light in a scene. All that reaches your camera's CCD is infrared light, which is what your camera will use to take the picture.
Here's the bad news: Infrared filters are considered specialty photographic items, and typically aren't available at your local photo store. You may be able to special-order an infrared filter, but these items are generally cheaper and easier to get from an online photo store. You can try one of these:
Adorama
http://www.adorama.com
B&H
http://www.bhphotovideo.com
An infrared filter will set you back around $50 to $75. These filters come in a variety of strengths, but I've found that practically any will do. Just be sure to order one that fits the thread size on the front of your digital camera; if you camera doesn't have screw threads, you may be able to order an adapter.

Shooting Alien Landscapes
When is the best time to shoot infrared photos? Like most ordinary photography, it's in the early morning or late afternoon hours. You can't shoot at night, of course, because there's little or no infrared light available to expose your picture. You'll find out very quickly that infrared photography is dramatically different from visible-light photography. The most important difference, of course, is that an infrared filter blocks nearly all of the visible light coming into the camera. The lack of visible light means that exposure times are much longer than usual. You might find your camera exposing pictures for a quarter-second or half-second in broad daylight--which means that a tripod is essential. There's so little light that you may run into another problem: It's hard to see through the lens. As a result, the camera's LCD is almost useless for framing your shot. The display will be very dark, and you'll have to concentrate hard while blocking glare on the LCD to see anything at all. If your digital camera has a "window" style optical viewfinder that doesn't get its information from the lens, you can use it to frame the scene instead. Since my digital camera--an Olympus e10--has a through-the-lens viewfinder, I can't frame my scene that way. Instead, I line up my scene without the filter, then I screw the filter onto the lens and take the picture. Obviously, I use a tripod for all my infrared photos.

Cooking Up Prints
Thankfully, your digital camera should handle all the other details for you. It can properly expose infrared pictures, for instance, and even focus using infrared. But when you get the images back to the computer, you may find that they have a relatively narrow dynamic range. In other words, there's not a lot of contrast. Load your images into an editor like Paint Shop Pro and use the Histogram Adjustment tool to increase the contrast and range. How to use the Histogram tool step-by-step instructions are right here:
http://www.pcworld.com/howto/article/0,aid,62724,tk,dfx,00.asp
After you tweak the image, you can leave the red tint or convert the image to gray scale. (In Paint Shop Pro, choose Colors, Grayscale.) Have fun with infrared photography, and be sure to try this technique out this summer when the trees and flowers bloom. You may feel like you visited Mars.