More after the jump.
The only telephoto I want to buy has a very dark cloud hanging over its head that prevents me from buying it: the Olympus Zuiko 150mm f/2. I desire it greatly because it is small, lightweight, and despite the odds stacked against it, it has proven to be an extremely powerful optical device. This is the telephoto for the otherwise-Leica photographer.
Unfortunately the Four Thirds system (sans Micro) is dying faster than film these days and as yet there are no Micro Four Thirds products that implement phase-detection AF (e.g. adapters with pellicle mirror, phase sensors embedded on the image sensor) on that platform. It’s a big deal for this lens because it’s old-fashioned, it wants to be told to servo to a specific distance at a specific time and not scan the space in itty-bitty steps the way contrast-detect AF does. That means the lens doesn't handle either moving subjects or video very well or those cameras.
It’s unclear what Olympus’ strategy will be for the final days of the E-system in general, and its lenses in particular. Will they enable E-system lenses to work on Micro Four Thirds cameras with phase-detection AF? Will they scrap the E-system wholesale and redesign (i.e. “Mk-II”) the high-grade lenses for contrast-detection AF instead? Without knowing how it will play out it’s hard to think about buying an E-system lens today, especial a high-grade lens like this one.
Thinking about it now, integrating phase-detection onto the image sensor sounds like a requirement for a professional mirror-less camera. It seems that everyone in Japan has a patent on this technology so it has got to ship in a product eventually, and Olympus is the company with the most incentives to do so. I really hope this is Olympus’ strategy.
Now returning to reality… humbug, I just don’t want to buy any of the Nikkor telephotos.