With the new OM-D E-M5 coming (hopefully soon) I have been contemplating some lenses and would like something for super telephoto work. I have considered the Panasonic 100-300mm but am now wavering on IQ and whether or not it can really do the job and I'd like something a little faster than f/5.6 at the long end.
My thoughts are the Zuiko 50-200mm f/2.8 - 3.5 as this seems like an awesome lens from everything I've read. One reviewer for the E-M5 even said the focus with the 50-200 on the E-M5 was decent so that would be a plus too. Has anyone used the Zuiko 50-200 with a 1.4x and/or a 2.0x TC? If so, what are your thoughts on IQ with those.
I'd prefer something that can AF on MFT but have also thought about some MF options like the Nikon 80-400mm f/4.5 - 5.6, but if the 50-200 with a 2x TC is about as good as the Nikon then I think I'd rather have the option of a fast 50-200 and a decent 100-400.
If you can think of anything else I'd be more than interested, I'd really like to spend no more than about $1500 so that takes out some of the more expensive options.
I can't give you a comprehensive answer but IMHO, the Oly 50-200 is a very sharp lens based on my experience using it on an Olympus E-1. I have version 1 of this lens. Sharpness remains high through the focal range. There seems to be a sweet spot somewhere around 70 - 100 mm but even at 200 mm, images still look great. AF is OK in good light and can hunt a lot in low light. The updated SWD version is supposed to be much better but I don't have experience with that one.
I'm sending you a pm on where you get more helpful advice. I'm not sure what AF performance you need for whatever you're shooting but, if you can get 'enough' AF, I would definitely keep the 50-200 on your list based on its IQ and light gathering ability.