August 23, 2014, 04:03:07 PM

Author Topic: 70-300L or 100-400L  (Read 1333 times)


  • Rebel T5i
  • ****
  • Posts: 109
  • Amateur, Enthusiast, Canonphile
    • View Profile
    • Flickr photostream
70-300L or 100-400L
« on: October 09, 2012, 10:14:18 AM »
I shoot with both a 7D and a 5DMkiii. I currently have a 70-300mm f4.5 - 5.6 DO IS USM, and am wondering if I should upgrade it to a 70-300mm f4.0 - 5.6 L IS USM or the 100 - 400mm. I have found the current lens a little soft on both bodies, certainly when compared to my 24-105L and even my 15-85 EFS.

The 100-400 has the attraction of an extra 100mm, but then it is a much older lens. My main use for this historically has been bird photography, and therefore it is better on the 7D. Can anyone comment?


5DMkiii, 7D, loads of glass


  • ********
  • Posts: 13883
    • View Profile
Re: 70-300L or 100-400L
« Reply #1 on: October 09, 2012, 10:27:06 AM »
If you don't really need the extra 100mm, the 70-300mm L is the better lens.  If you do need the extra reach, the 100-400mm is the way to go.  For birds, you almost always need the reach.  I'd go with the 100-400mm. 

Most (but not all) of my shots in my Flickr Birds and Wildlife sets are with the 7D and 100-400mm (you'll see a couple with the 7D and 70-300 DO in there, too).
EOS 1D X, EOS M, and lots of lenses
Flickr | TDP Profile/Gear List