CyberDyneSystems wrote in post #19404033
Excellent! Really top quality image.
The old 400mm "pocket rocket" is an amazing lens!
I could not part with it back when i was still shooting the version 1 100-400mm "trombone"
It had noticeably better image quality, and MUCH faster, more confident autofocus. I was always left having to decide which was best for each use, as it was no good at all for 100-399mm

IMHO, the Version II changed a lot of that. IQ is now so close as to make no difference (I am sure you are correct that the prime may have the edge) and if I recall correctly I was pretty convinced the modern AF motor was slightly faster. I finally did sell the 400mm, but I do miss it's lightweight and ease of use.
It was that light, back when lightweight long primes was not a thing. Imagine f they applied some of the more recent weight savings to a modern version of this lens?
Jake,
They are virtually the same for sharpness but with my 100-400ii and the 400, at this point I give the sharpness edge to the 400 f/5.6, maybe my mk II is a not quite as good, not sure, was always and still am happy with it. BUT you are right the AF is faster on the 100-400ii, it is noticeable. BUT the light weight and where I use it at the pond, it is a winner. It is another horse for the stable
Taxboy wrote in post #19404041
Excellent shot. Can I ask were you using mechanical or electronic shutter please
This was H+ on the mechanical shutter. I have found the ES with hummers to give rolling shutter and can ruin a good shot. The noise doesn't scare them from 15 feet away but any movement does. I am shooting CRaw and get about 4 seconds with H+ and the shutter held down, about 60 shots., same with ES, only time I have used the ES 30fps has been with burst mode.
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