Thought I'd treat you all to our GKF. In this shot he was about 40m/131" away! He's obscured by the branch so not a memorable image, record shot imo.
The GKF is the largest kingfisher in Africa, where it is a resident breeding bird over most of the continent south of the Sahara Desert other than the arid southwest and is 42–48 cm (16.5-18.9") long! Thats from your fingertips to about halfway down your arm. This large species feeds on crabs, fish, and frogs, caught in the typical kingfisher way by a dive from a perch.
What makes this shot interesting is that I took it with my 500mm Vivitar Series 1 Mirror Reflex Lens, in a bird hide on a bean bag. On APS-C (small frame) sensors that gives you a whopping 750mm focal length at f/6.3! Manual Focus, manual exposure, fixed aperture "lens" and best of all no CA :) (Chromatic Aberration=Purple Fringing on contrasty edges often found on cheap long focal length glass lenses, like 75-300mm/18-250mm f/4.5-5.6 type lenses)
Bah humbug! to all the nay-sayers of mirror lenses. (I'm awaiting the BG (bokeh) circle of confusion comments, specifically about a mirror lens phenomenon...) :) It is very useful for Paparazzi style street work too, not just wildlife.
I have no idea what you're going on about with the lens (I'm just not quite that savvy) but I love the picture. And I LOVE the bokeh! It does exactly what it is supposed to, which is show off your subject. Hard to tell how big he is, but gosh he's pretty! Thanks for the info!
You'll get some good comments on this I bet Harvey, it's beautifully shot. I like the angle, shooting up like that has added an interesting dynamics as we view the bird looking out from its perch. And yes, lovely blurred background. Cheers, Michele