I've always been a bit fascinated by digiscoping. For those who are out of the loop, digiscoping involves taking images through a spotting scope rather than a camera lens. The advantages are obvious. A spotting scope provides magnification equivalent to a lens of 1,250 to 3,000mm.
Not to mention a spotting scope is much smaller and far less expensive than a telephoto lens. Plus spotting scopes are sealed, waterproof and filled with inert gases like nitrogen. If your spotting scope falls in the lake, you fish it out and wipe the mud off. That's not what…
via Imaging Resource News Page http://www.imaging-resource.com/news/2012/11/08/digiscoping-dissected-can-swarovski-scopes-pinch-hit-for-a-super-tele-lens