I’ve been searching for comparisons between these two lenses and haven’t been able to find much beyond the obvious weight difference. What I’m most interested in is the difference in autofocus speed and accuracy between the two with and without the version III teleconverters. I was wondering if anyone on here has owned or owns both and can comment from experience on how much of a difference there is. I’ve used the 2x III on the 400 DO II as well as my 600 II and I found it to be pretty great on the DO and borderline unusable for flight with the 600. I’m wondering if the difference in weight between the two lenses’ focusing groups is the reason for this or if it’s because of the significant difference in focal length.
Tony I can't help with a comparison of the 2 400mm's but I do own the 400mmMk III and the DO II and owned the 600mm II. The tracking with the 2x on the 400mm Mk III blows away the DO for flight work and the 600mm II. I use mine at 800mm most of the time. It has been the best lens with extenders I have ever used, the lens at 2.8 is outstanding. The weight balance is amazing too.
Here is a recent one at 800mm. My Flickr site has tons of shots with the 400mm Mk III, I have an album for that lens too.
No idea what your post means, are you saying you like the 400DO II better for flight with using the 2x? Fine if you do, I have a few with flight myself using the 2x extender, it is a great lens and as a bare lens or with the 1.4x it is great for BIF work. However the 400mm MkIII will eat he DO II's lunch for flight work using the 2x extender hands down.
Thanks for the sample Rob! I’m so impressed by the performance of the 400 III with the 2x, especially for tracking flight. I’m hoping CPS will have the 400 III on the evaluation list soon so I can give it a try to see for myself. It’s strange how little info/reviews there are online about the AF performance of the II with the 2x on it, wondering if that’s indicative of its performance...
RobAmy wrote:
No idea what your post means, are you saying you like the 400DO II better for flight with using the 2x? Fine if you do, I have a few with flight myself using the 2x extender, it is a great lens and as a bare lens or with the 1.4x it is great for BIF work. However the 400mm MkIII will eat he DO II's lunch for flight work using the 2x extender hands down.
