Buying a digital camera: shopping for a digital camera? Confused by all the choices? Here are some tips from our technology editor

Tools of the Trade, Nov-Dec, 2002 by Joe Stoddard

Size. It's a pretty good bet the camera you can tuck in your pocket will be the one you use most often day-to-day. If you plan on using your digital camera to document your jobs, smaller and lighter is definitely better.

Resolution. The maximum size of the image a digital camera can capture is stated in "mega-pixels" (millions of dots), similar to the way your computer screen is rated. A 2-mega-pixel camera can produce excellent 4x6 prints and good 8x10 prints and is more than good enough for any Internet or e-mail application where small file size is a must. A 3-mega-pixel camera produces excellent 8x10 prints and good 12x16 prints. Right now, a 2- or 3-mega-pixel camera provides the best price-to-value ratio for most contractors.

For serious photographers, higher-resolution digital cameras are available. A good 5-mega-pixel camera can rival 35-millimeter film in terms of image quality. If you use a CAD-assisted estimating system like CADestimator (www.cadestimator.com) or need very high quality images to do architectural rendering, import into CAD systems, or create large-scale presentation printouts, these cameras are definitely worth considering. There is a downside though: High-resolution digital images create gigantic file sizes that are hard for plain-vanilla computers to handle. If you're planning on processing the images yourself, make sure your computer hardware is up to the task.

Storage. Compact Flash, Memory Stick, and stamp-size Secure Digital Cards are all types of solid-state storage used by digital camera manufacturers. Despite what the salesperson at Circuit City may say, the solid-state format your camera uses doesn't make that much difference, because normally you'll be connecting the camera directly to your computer or printer using a special cable to transfer the images.

Zoom. Many cameras combine optical zoom lenses with digital zoom for a better-sounding zoom spec. Digital zoom degrades image quality, so the optical number is the one to look at if you're concerned. Remember, you can always re-size and manipulate images once you download them, so zoom really isn't as important as it is with a film camera.

Extra Batteries. Some digital cameras use special rechargeable batteries, which have limited storage life and tend to run out of gas when you need them the most. Unless you want to lug around a bulky battery charger, consider purchasing a couple extra rechargeable batteries when you buy the camera.--Joe Stoddard is technology editor for HANLEY-WOOD'S TOOLS OF THE TRADE. Contact him at jstoddard@stny.rr.com.