Digital Focus: Take Wild, Weird Infrared Photos

Take infrared shots with your digital camera, learn all about megapixels.

Dave Johnson

Feature: Shooting Infrared With Your Digital Camera

Your horoscope says that you should do something daring and adventurous, but skydiving is just plain out of the question. That's okay, because this week I'm going to suggest that you try something totally off-the-wall with your digital camera. Just for fun, let's try shooting some pictures in a completely different part of the color spectrum: infrared.

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.

Testing, 1... 2... 3...

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 particular newsletter 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 such as Adorama or B&H.

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. I discussed how to use the Histogram tool in a previous newsletter.

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.

Dave's Favorites: E-Mail Photos From Your PDA With BugMe

If you're like me, your office is decorated with little yellow sticky notes reminding you to file your reports, call the boss, and buy more yellow sticky pads. BugMe is an electronic equivalent of those colorful little notes for your Palm PDA. You can jot messages, sketch drawings, and even attach alarms to your notes for timely reminders.

So what does all that have to do with digital photography, you ask? Well, BugMe Messenger--BugMe's big sibling--lets you send your notes from a wireless-enabled PDA to other PDA users via e-mail. And since BugMe is compatible with a number of digital cameras for the Palm, it lets you wirelessly e-mail digital images as well. If you have a Kodak PalmPix or an EyeModule for the Handspring Visor and a wireless Internet account, for instance, you can take photos with your PDA while out of town and e-mail them immediately to the office or home to the family. You can even annotate those images with Graffiti text, your own handwriting, or free-form sketches.

BugMe Messenger costs $29.95; you can download a free trial from BugMe.net

Q&A: The Definition of 'Megapixel'

What is a "megapixel?"

--Fred McClay, Nampa, Idaho

That's the standard unit of measure for digital cameras, Fred. Simply put, a megapixel is a million pixels, and it's used to refer to the resolution capability of your camera's CCD. The megapixel rating tells you how large the resulting photos can be and still retain good display quality. That information lets you know how large your photos can be printed on a typical ink-jet printer.

One-megapixel images usually correspond to 1152 by 870 pixels, while 2 megapixels give you 1600 by 1200 pixels. A 3-megapixel camera produces pictures that measure 2048 by 1536 pixels.

As a rule of thumb, you can print 2-megapixel pictures as large as 5 by 7 inches on an ink-jet printer, while 3-megapixel images can be enlarged to 8 by 10 inches. If you try to print a digital picture too large for its resolution, the individual pixels become apparent in the final print, making it look jagged, blurry, or pixelated.

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 $10 and $100.

A gentle reminder, folks: We disqualify some really wonderful pictures every week because the submissions don't follow the rules. Be sure to include everything we ask for in your e-mail message, including a description of your picture and your complete contact information, or your entry is wasted!

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 regs.

This week's Hot Pic: "Two Corners," by Kevin C. Cox, Glendale, Arizona

Kevin writes: "This is a shot I captured with my Olympus C-3000 as I strolled around downtown LA after a morning rain shower. I caught a glimpse of clear blue sky between skyscrapers and grabbed the shot."

We want your feedback! Send your comments, questions, and suggestions about the newsletter itself to comments@bydavejohnson.com. If you have a question that you'd like to see answered in the weekly Q&A, send it to question@bydavejohnson.com.

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