Sigmonster

[Kenneth Sky]

a more practical alternative may be to use a Zeiss Diascope which is cheaper but harder to set up with an SLR t-adapter or lighter by far using their just announced digiscoping eyepiece

[Andrew Teakle]

It's good to finally read a review of this lens here on LL. It's an intriguing concept and the few reviews I have read all rave about its performance (sharpness & AF). It is not something I would like to lug around all day, but sure would be a gem when you want ultimate reach. Consider a 1280mm f5.6 (35mm equiv) on a 30D or 400D! That's some lens.