If you're just joining us, I've been writing a series of entries for neophytes with DSLRs--mainly people who have been too scared to move their camera off "AUTO." Think of me... think of us... as your online support group. We want you to succeed and start exploring what your camera can really do. Your knowledge is a whole lot more important than which specific camera you're gripping.

If you've had your camera any length of time you've probably pondered buying a new lens or lenses and you've been floored by the choices available. A friend of mine who worked his way through college selling men's suits says he used to bring them out one-at-a-time because with too many choices people would buy nothing at all! No one wants to make a mistake. It's that way with lenses. It would be easier to make a purchase if there were fewer to choose from.

So, what's it going to be? I'm not going to steer you toward a specific brand or size, but I do have some advice to help you narrow your choices. I can see this is going to take more than one entry to cover properly, so lets start with prime lenses versus zoom.

A prime lens is a lens with a single focal length. A 50mm lens is a prime lens. A 17-55mm lens is a zoom lens.

Why would anyone ever buy a prime 50mm when that 17-55mm or 18-125mm zoom covers its function and a lot more? It's simple. Prime lenses are less complex, make fewer compromises and are more often than not faster and sharper.

If you're just getting here, faster means the lens aperture can open wider (a lower numbered f-stop) allowing more light to hit the sensor. Simply put, fast lenses are better when light is low or the action is fast and needs to be stopped. Faster lenses also have a shallower depth-of-field, meaning the portion of your shot which appears to be sharp in the image will be smaller. If you're new at this that might sound bad. Trust me here, shallow depth-of-field is mostly considered a good thing. You'll also appreciate prime lenses weigh less--especially if you'll be carrying it all day.

Zoom lenses are more versatile. A lens that can cover 18-125mm scratches a lot of itches. In most cases the larger the ratio between longest and shortest focal length the slower the lens (higher the lowest usable f-stop) will be. You're almost always giving up lens speed with a zoom.

In some brightly lit situations you might not care. Bright sunlight was the only way I could get this football photo with my cheap and slow zoom. All the professional photographers at that UCONN/Army game were carrying much faster glass. They don't wait for perfect weather to shoot as I did. I had a terrible case of lens envy. Size matters.

If you want need a long lens to shoot birds or sports under varying light conditions or car racing, you're going to find lens speed is often the difference between a good or great shot and no shot at all!

Nowadays many lenses and some camera bodies come with built-in optical stabilization which buys back some of what a slow lens costs you. Stabilization keeps unsteady hands from ruining shots but it won't stop the action you're shooting! It wouldn't have saved my football shot on an overcast day. When a slow lens forces a slow shutter speed action will be blurry--period.

Your decision on what type of lens to get depends on your needs. The good news is when you figure that out there is undoubtedly already a lens that can do it!