Of the lenses mentioned I would take the 300/4 with a
teleconverter over the 400/5.6 because this combo
offers both more flexibility and focal length than the
400/5.6 and is just as sharp.

As far as the 100-400 zoom that people have mentioned
I would suggest that perhaps you look at just how
important the IS is going to be to you. While there
are many people out there who are happy with the
100-400 zoom there are probably an equal or greater
number of people who have given up on this lens
because of image quality and performance issues. One
problem Canon has is with its quality control and
there are just as many bad copies of this lens
floating around out there as there are good ones, or
so it seems. If it were my choice I'd get the Sigma
50-500 over the Canon 100-400 as image quality on the
long end should be comparable if not slightly better
in the Sigma and it gives you extra reach in focal
length if you're shooting birds.

Michael Dossett

Michael Dossett
Corvallis, Oregon
www.Mdossettphoto.com
phainopepla at yahoo.com

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