Older cameras and digital SLRs (single-lens reflex) cameras, and those cameras with detachable lenses often protect the lens with the classic lens cap. Imagine, you've just bought a $700 telephoto lens and you drop or lose the lens cap. Now, there's nothing between that forgotten spare key at the bottom of your camera bag and your new lens' delicate outer glass.

It ain't pretty.

This is where we tell you about the best two bucks you'll ever spend. Every lens I own that needs a lens cap is equipped with a lens cap leash, as shown in Figure A.

FIGURE A

This is one I bought recently at the local Ritz camera. Most camera retailers have them. Click picture for a larger image.

This leash consists of an elastic band tethered to a string, tethered to a little round plastic nub that comes with thick, double-sided sticky tape. Whenever I get a new lens, I get one of these doodads as well. I wrap the elastic band around the lens and affix the sticky tape to the lens cap. Then, whenever I take the lens cap off, it hangs nicely from the camera and doesn't get lost.

I bought a 70-300mm lens recently and picked up the leash shown in Figure A for two bucks from Ritz camera, one of the few remaining camera retailers here in Central New Jersey. I've seen these things in a variety of brands, and most camera stores will stock something similar.

If you've got nice lenses with lens caps, you owe it to your gear to pony up the two bucks and protect your lens.

For more than 20 years, David Gewirtz, the author of Where Have All The Emails Gone? and The Flexible Enterprise, has analyzed current, historical, and emerging issues relating to technology, competitiveness, and policy. David is the Editor-in-Chief of the ZATZ magazines, is the Cyberterrorism Advisor for the International Association for Counterterrorism and Security Professionals, and is a member of the instructional faculty at the University of California, Berkeley extension. He can be reached at david@zatz.com.