It really depends on the kind of shooting you're accustomed to. Do you usually stay wide? Do you need a lens with a high zoom ratio? Maybe you want something with image stabilization?

I don't know what camera you're getting, but I believe all the Canon DSLRs now come with a stabilized, autofocus 18-55mm kit lens. That's a decent lens, but because of its computer-controlled aperture, there is a bit of a flicker whenever you zoom, so if you're using that lens you should be prepared to set your focal length before you start shooting.

I'm a big believer in prime (non-zoom) lenses for most work; they're lightweight, sharper, and better in low light than most zoom lenses. A good kit of primes would consist of a 50mm (this is your middle-of-the-road focal length, similar to what the human eye sees), an 85mm, a 100mm, and a 24mm. For added variety you could throw in a 32mm, and if you're really rolling in the dough you could spring for an ultra-wide lens like a 16mm. If you're really into the long-lens look you may want to consider a 300mm.

If you don't need autofocus, you can save money by buying older lenses and adapting them to your camera body. Again assuming you're getting a Canon, there's a company called Fotodiox that makes adapter rings to convert Nikon lenses and Pentax screw mount (M42) lenses to the Canon EF mount.

NOTE: avoid at all costs older Canon lenses that use an FD mount; they won't fit your camera and cannot be adapted without the use of an expensive conversion lens.

I myself am a big fan of older Nikon lenses; the E series being the gold standard. If you keep an eye out for them on eBay you can usually get a pretty good deal, just be careful that you're buying fully functional lenses without any scratching or fogging.

One particular recommendation: Nikon's fast 50mm (opens up to f1.4) when coupled with Canon's remarkable low-light performance will allow you to get great-looking footage in very low light, a real plus if you're shooting documentaries.

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Andrew Gingerich
Exploding Goldfish Films
Check out my blog at http://www.exgfilms.com
and my reel at http://portfolio.exgfilms.com

you just saved me alot of research. thanks alot.

" see things through my eyes "