[davidmanze]

  The sole route now is to out-date their own current optical designs............ and replace them with larger heavier and more expensive ones to compete with the likes of Sigma and Tamron and the unlikely new member into the AF market, Zeiss.

 

 However, are we seeing a stabilization vis à vis mirror-less now, re Samsung?

 

   Putting 4K into DSLRs would go some way to stopping the rot!