Male Siskin

This photo was taken in my garden during April 2009.
The technical information is as follows.
Camera - Canon EOS 50D
Shutter speed - 1/1000
Aperture - f6.3
Lens - Canon EF 500mm f4.0 L IS USM plus Kenko 36mm Extension Tube
Focal Length 500mm
ISO 400
Tripod