nick c wrote in news:463c0b8b$0$4667
:

I would like to add:

Canons 70-200 f2.8 L IS lens coupled to Canons 2x telextender attached
to a 30D (or 20D) gives excellent results at F5.6 at an equivalent
640mm; keeping the use of Modes 1 and 2 IS. This setup is what I use
for wildlife photos; still retaining the basic 70-200 for conventional
use.

I have never seen a sample from the 70-200 f/2.8 IS with a 2x TC that
looked anywhere as sharp as a good 100-400 @ 400.

TCs are good for getting a little more subject detail out of a given lens;
it is not a substitute for lenses that do the same thing without TCs.

--


John P Sheehy