Right surveillance needed, even for leaky roof

Odd as it may sound, the cameras have turned into an extra set of eyeballs that see everywhere at once. Most cameras are in fixed positions — monitoring doors, driveway, mailbox, living room — but I've reserved a few that move from place to place to check out something specific. One lesson so far: Know the limitations of each type of camera.

For example, a few weeks ago I had a roof leak into my kitchen. This pesky leak had appeared before, but nobody could figure out the cause.

Cameras to the rescue. We placed a few low-cost cameras in the attic, set the digital video recorder to record when it saw motion, and waited for the next rain. The attic drip cams really helped to locate the problem and diagnose what had to be repaired.

But not all video security cameras are created equal. Price doesn't always determine the quality or features, so check out this handy list of what types of cameras are available.

My favorite security camera has two modes: color during the day and an automatic switch to black and white at night for much better viewing in low-light conditions. Another feature that I like is being able to change the lens to get a far or close-up shot.

And the perfect camera must respond to infrared light. This light, not visible to the human eye, can light up a pitch black room for a camera that is running in black and white mode.

Two other factors determine quality. The resolution, usually expressed in horizontal lines, and the lens quality make a big difference in what the camera can see. Many video cameras use 380 horizontal lines, but I prefer 420 or 480. As for the lens quality, the bigger and clearer, the better. Some are fixed at one focal length, while others let you adjust for a close-up or faraway picture.

Confused? Well, there is a class of cameras that takes away some of the complexity. Many IR cameras can switch from color to black and white, have automatic focus, sometimes are outdoor-ready and generally cost less.

The IR lights usually surround the lens, so when it gets dark, the lights make the room look as if there is a light on. If you can get the picture you want, these pre-assembled cameras are great.

And there are even wireless cameras. I recently tested several small ones.

While the idea is great, the picture isn't as good as a wired camera.

As for the price of small video security cameras, there's a big range. You can spend more than $500 per camera or as little as $30. Or, if you aren't sure you want to invest in a multi-camera system, you can start with an inexpensive Webcam and use your PC as a host. Logitech and other Webcam makers usually include a security feature that comes with their cameras.

As for video security cameras, Electronic Parts Outlet on Fondren has a good selection. My favorite online store is SmartHome, at www.smarthome.com.