At early this year, we first posted rumors about Sony will announce a 400mm super telephoto prime lens in 2017. Now according to SAR, a new super telephoto prime lens is rumored to be announced soon. This lens will be a 400mm prime lens, the aperture of this lens hasn’t yet confirmed, it will mostly like f/4, or even f/2.8.
If this lens is Sony FE 400mm f/4 GM lens, it will be a compact, light weight prime lens. If this lens is much faster Sony FE 400mm f/2.8 GM lens, it would be very large, and price will be very expensive.