An oft asked question I hear is: if one is deciding on between the Canon 24-70 f/2.8 and the Canon 24-105 f/4 IS, which one is better?

Well, the answer is: it depends. For me personally ( I own both), I like to use the 24-105 when I travel on vacation and/or am shooting outdoors. I want to pack as light as reasonably possible when traveling, which means limiting the number of lenses I bring with me. I’ll always bring an ultra-wide (my 17-40 f/4) and then the remaining lens choice is between the 24-70 f/2.8, 24-105 f/4 IS, or 70-200 f/2.8 IS. The 24-105 is my choice since it’s in between the 24-70 & the 70-200 as well as being the lightest of the 3.

I’ve learned not to lug the 70-200 along with me unless I know I will specifically be shooting in a situtaion where I will need a long zoom. Years back I brought it with me on a trip to Paris as well as to Thailand — I didn’t use it once in either. I brought it with me to Playa del Carmen (near Cancun, Mexico) and Costa Rica, though, since I was planning on shooting wildlife.

When I shoot indoor events, I use the 24-70 f/2.8 since it is faster glass. Coupling Canon’s f/2.8 and faster lenses to a 1-series body (eg. my 1D MK II) activates more cross-type AF sensors which, if you’ve ever shot in low light, means that you’ll get faster focusing and less hunting. Nothing like waiting for your camera to lock focus in low light, especially when shooting fleeting moments of people.

24-105 Pros:

  • Image Stabilization
  • longer zoom end (105mm vs 70mm) — there are so many tims when I’ve used the 24-70 and said to myself, “if i only had just a little bit more reach”
  • lighter weight vs. the 24-70

24-105 Cons:

  • slower focusing in low light situations due to f/4 (at least on 1-series bodies – not sure if the non-”pro” bodies are the same way)
  • vignettes & barrel distorts at the wider focal lengths more than the 24-70, but you might not notice unless comparing side-by-side, though it can be automatically corrected in post-processing using something like the superb PTLens application
  • darker viewfinder image vs. the 24-70

24-70 Pros:

  • faster glass, which means better/faster focusing in low light
  • brighter viewfinder image

24-70 Cons:

  • on a 20d/30d/5d feels a bit lopsided due to it’s extra weight unless you have the optional battery grip.
  • heavy
  • no Image Stabilization