Nikon can use fastest Sony 60Mp FF sensor (see http://www.personal-view.com/talks/discussion/20967/new-fast-sony-ff-sensors-coming):
And yes, we can see both 8K video and 4K 60fps video with around 90% probability.
Nikon will present camera before Tokyo Olympics and will position camera as top featured model.
But remember that rumors are that Sony will come with their own 60Mp 8K camera before Nikon.
My talks show that Panasonic fully abandoning m43 (advanced cameras and almost no new glass planned) is related with the fact that Sony do not want to make 8K m43 sensors despite Panasonic early requests.
I suppose Fuji X APSC is safe for now due to Sony using the same size in many of their cameras?
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