According to the latest rumors from FT, OlympusM.ZUIKO DIGITAL ED 300mm f/4 PRO Lens will start shipping from Nov 15, 2015. But there is yet no info about the price and specs of this lens.
Reminder: Olympus will also announce another two PRO lenses Olympus 8mm f/1.8 Fisheye PRO and 7-14mm f/2.8 PRO lens.
Source:FT3
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