Your help please.

I began digital photography only 2 years ago and have 'progressed' to a Canon 20D + Sigma 75-500 zoom lens. My passion is bird photography and I wish to get closer, especially to the Sea Eagles on the Isle of Mull, Scotland. Sigma make a 300-800 zoom but, oooooooh the price!! Any suggestions from you 'experts' would be gratefully accepted. (I've tried a 2x convertor, but I'm not very happy with it - it wasn't expensive!) and of course the old axiom - move closer you fool - not possible. Thanks guys, Reverend Tony Budell (England)

It might be cheaper to hire a boat, Tony

Trik

On value for money and optical quality wise , I've seen people get stunning results using a Canon 400mm f5.6 with a 1.4x canon or kenko pro extender , whilt on paper they dont appear to give that much of a reach advantage over your sigma , I would contend the optical quality would be better and allow for a nice crop.

say one for me reverend I need the help

John