"Roger N. Clark (change username to rnclark)"
I agree with this assessment. A great starter wildlife
lens that gives great results on Canon DSLRs is the
300 f/4 L IS (about $1100) and add a 1.4x TC (even a Kenko
pro 300).

The trade-off that I went with was the Canon 70-200L f/2.8 IS with the
Canon 1.4x TC, which functionally makes it into (roughly) a 100-300 f/
4 IS zoom, with the "theoretical" capability to drop back to the f/2.8
if its getting really dark.

I say "theoretical" because while I had the capability, I don't recall
ever really using it on this trip...because it takes time, which you
often didn't have much of when in fading light. Instead, I jacked up
the ISO & sandbagged, which is for example the approach used for this
image, where the remaining ambiend light resulted in an Exposure
Value (EV) of only around 5:

http://www.huntzinger.com/photo/2006/tanzania/banda-
elephant(4141).jpg

EXIF:
Camera: Canon EOS 20D
ISO: 1600
Shutter/Apertu 1/30 @ f4
Focal Length: 98mm
Lens: EF 70-200L f2.8 IS USM with 1.4x


In my opinion, IS makes the difference in
shooting from a safari vehicle, especially near sunrise
and sunset.

Agreed. Particularly in fading light, time can easily be of the
essence, so a quick "move and shoot" from any reasonably well
supported position has value.

Overall, nothing's perfect...it would be nice to always have maximum
flexibility options, but that also requires a lot more money to clone
the additional hands to handle all of the stuff ;-)


-hh