Alien Clumps choreographed a chorus line of high-kicking electrons to
spell out:

For my 20D that I intend to purchase, I am having an excruciating,
painful time trying to decide which lense to put into my outfit.
I like the 100-400 in that it has IS, and of course, zoom.
I like the 400 5.6 because it is prime, sharper lense, etc.
I saw numerous pics posted on various websites for each lense. They
are all outstanding (the oustanding ones that i viewed).
I love closeups. I intend to do some birding along with other nature
shots. No sports. No archetecure. Pure nature.

So I need some more opinions on the 2 lenses plus some experience. I
sure do appreciate it!


This one is a toughie

From Art Morris's site:
http://www.birdsasart.com/faq_1-4is.html
http://www.birdsasart.com/faq_1-4isor4f56.html

I bought the straight 400 after considering the same question. In my
situation though, I already have a 70-200 and just really needed the
extra extra length at 400. The 100-400 is flexible on its own though,
and much less to carry around. I'm still perhaps a little bit
ambivalent, but I like toys
While you can use the 400 without a tripod, if you are planning on having
a tripod along that evens things out a bit between the two lenses.

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