Will,
You will find out that the general consensus will be that the 24-105mm for a FF body and the 15-85 for a crop body like your 60D. The 24-105mm has a longer reach and indeed, from your description, it sounds it would fit your bill better. However, not knowing whether you will be taking some indoor shots or not and how much, if yes, the 24mm end on a crop body can be a little bit too tight. For outdoor shots, most of the time, you can do zooming by feet but indoors will be a different story. At the end, I would seriously consider the 15-85mm if I were you. The long end of that lens is a tad shorter than the 24-105mm but still not bad. For safaris, you will find out fast that neither will have enough reach .
You still have time to decide and play with either lens before your trip. Play with both. You can rent lenses or if you feel lucky you can buy them used, try them out and sell whatever you decide not to take with you on the trip.
Enjoy the trip,
Joshua
Plesy
Sep 24, 2011 at 12:13 PM
Previous versions of AGeoJO's message #9944883 « Canon 24-105 vs. 15-85 »
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