Lenses. They're your most powerful photographic tool, if you know how to harness their mighty power (and manage not to shatter them). And you know what? Chances are that even if you think you're a lensmaster, you've still got a lot to learn. And these guys are going to teach you.

Vimeo's Blake Whitman and all-around camera genius Vincent LaForet learn you good in the video-sharing site's original series, starting with the basics, leveling up to focal length, and capping off with depth of field. You're not going to find a better 15-minute photography primer, especially not for free, and double-especially not with a viking and an astronaut peaceably co-mingling. [Vimeo]