jonnyapple said:
A more reachable goal is to become an astronomer, and the cameras are sweet. Take the Keck observatory in Hawai'i: two 17000mm f/1.8 lenses (that's not a typo: 17600mm focal length and 10000mm aperture, so f/1.76, but who's counting?), and one of the interchangeable sensors is the NIRC, which is sensitive enough to see 1 candle's light at a distance from the earth to the moon.
I'm friends with quite a few astronomers and I can tell you that most of them wouldn't care about going out in their pajamas and love to take pictures of planets. But honestly, I'd never do observational astronomy because the hours are usually bad.
If I may nitpick, the Keck's primary mirror has a 1.7 meter focal length but I don't think it can image with it. Combined with the secondary it's a f/15 Ritchey Chrétien with a focal length of ~150,000mm (150 meters).
Amateur astronomy is a strange hobby when you consider it is usually sitting in the middle a cold dark field late at night. For the pros today it's a little easier, They send the observation plan to the computer and pick up the data the next day. Then spend 6 months crunching the numbers.