> On Wed, 25 Feb 2004 [EMAIL PROTECTED] wrote: > > > are not so good stopped down past f/5.6 or so. Of course shooting > > a 200/2.0 at f/8 is madness! > > Why? > > Kostas (genuine question)
1) The Nikkor 200/2.0 EDIF at least is optimized for performance at or near f/2.0. According to those people who have the money to play with such things its optical performance at f/8.0 is inferior to other 200mm lenses. I can't see that the Canon would differ in this respect. Large-aperture lenses optimized for performance wide open (say the 85/1.4 AF or 28/1.4 AF nikkors) do not seem to compete well at middling apertures with more traditional lenses optimized for performance at those apertures (say the 85/1.4 MF and 28/2.8 MF nikkors). 2) The Nikkor 200/2.0 and Canon 200/1.8 are big, heavy, expensive lenses on par with 300/2.8s. It is very rare that I find a shooting situation where I expected to be working at f/8 and find myself working at f/2, or vice versa. I wouldn't carry a 200/2 unless I needed the large aperture, and if I could afford a 200/2 I could certainly afford a 200/4 to carry most of the time. I've actually thought about a 200/2.0 but without AF I wouldn't have a prayer of getting much in focus--the 300/2.8 has little enough depth of field wide open. So, a 200/2.0 at f/8 is going to be a pain to use and give you inferior results compared to a 200/4 or 200/2.8 at that aperture. Of course it'll probably do better than trying to shoot a 200/4 at f/2! DJE
