I do think that theIQ difference between24-105mm and 24-70mm is more significant than these posts suggest. Check outthe 24-105mm, http://web.canon.jp/imaging/eosd/eos5dm2/downloads/2_landscape.jpg. I don't have a comparison, but I think this helps to put into perspective what you are seeing in ISO 112233 charts.


Also check out the difference between the 24-105mm at 105mm VS the 70-200mm at 100mm.


Not saying the 24-105mm is bad, just the24-70mm isbetter.