« on: December 19, 2014, 09:46:07 AM »
I think apart from a rotating zoom (to which people seem to have mixed feelings) the usability with the TCs as confirmed by the MTFs, a reliable and more powerful IS, along with the much improved IQ is a sufficiently good reason for the widespread welcome this lens is getting.
Seems like the only thing missing is the much improved IQ. Roger's initial, cursory tests over at the rental place indicate it's only around 4% sharper on average. Of course there are other IQ considerations like flare, CA, distortion, contrast, color reproduction, etc., but 4% better sharpness isn't exactly a slam dunk.
To be clear, I'm looking forward to getting this guy and I want to love the heck out of every aspect of it. But 4% pales in comparison to the 40% improvement of the 400 DO II over its predecessor.
As I keep telling people, the old one was very good optically, but only under ideal conditions (IS off or stopped down a stop). The new one seems to be massively better under regular high stress conditions (wide oopen with the IS in, and in resisting flare and CA.
The mkI 100-400L has some notoriously bad copies out there. I've tried a number of copies over the years. Back in early 2008, I tried a copy which was just awful. Soft every where and it wasn't the AF system....something in the lens alignment must have been really out of place. Earlier copies which I had tried were like night and day on comparison. When I chose a 400L f5.6 over a 100-400, there were a few reasons why. The AF on every 100-400 which I tried was pretty slow, especially in lower light. I found the push pull at 400mm caused the lens to unbalance on a tripod and the 2 stop IS wasn't that great.
But that was then and this is now...the new lens looks like it's address all these issues and it's got slightly better IQ than the sharpest and best 100-400L's which came off the Canon line. It's it's reliable, sharp, quick and accurate AF with a great IS implementation and it's handling works better...then it's a worthy successor!
Will I be buying one? Not yet, I'll wait until the prices have stabilised a bit more.