I have head and hand tremor from a disorder of the central nervous system called "essential tremor" or "benign familial tremor" or "non-Parkinson's tremor." I take beta blockers to limit the shakes, but they don't eliminate the problem.
After finding some shots with my 24-70 a bit soft -- depending on how bad my tremor was at any given moment -- I bought the 24-105 IS and tested the lenses side by side. For me, the difference was so significant that I no longer own the 24-70. My shots of a static subject at 1/50 with the IS lens were sharper than the same shots at 1/125 with the non-IS lens.
The 24-70 offers cleaner bokeh, but not so much cleaner that I'd switch back. And of course, I occasionally miss the f/2.8. I use the 24-105 mostly for travel, mostly outdoors, or for indoor flashed photos. For me, it's an excellent event lens. When I need f/2.8, I use other lenses.
I've found that IS also helps me with action photography. True, it doesn't freeze subject motion. But it does (mostly) freeze camera motion which, even at high shutter speeds, can add blur. Those of you whose hands shake only on the morning after will just have to take my word for it.
What works for me may not work for you, but I hope it helps with your decision.
jkickhofel wrote:
That seems like a very sweeping rule - I can't imagine 1/24th getting a very good imagine when the sun is blasting your frame on a nice day - unless I stopped way way down?
1/FL is supposed to be a minimum shutter speed. Obviously you can increase the speed if you want to and have the ability to do so.
Indeed I am using a crop at the moment, I have been looking at the 17-55 IS, but I ask mostly because I plan to upgrade to a FF and want to get things straight before I do so.
jkickhofel wrote:
Indeed I am using a crop at the moment, I have been looking at the 17-55 IS, but I ask mostly because I plan to upgrade to a FF and want to get things straight before I do so.
Then I would deffenately get the f4.
Assuming you have bad hand shake, have you ever considered moving to Pentax/Sony? Sony makes a decent FF slr with image sensor based IS.
From what I have used they are not as good as Canons in-lens stuff (and brand quirks made me switch from pentax back to canon), but if you have hand shake, it would make the results from prime lenses much more enjoyable.