Originally posted by Na Horuk Ricoh (or rather, Pentax) already has plenty of camera mounts. Q, K (APSC and FF), 645 (crop and full), and even some legacy mounts like 110 and 67. I don't think it would be wise to make yet another mount. And it would be even worse to "sell out" and join another company's mount. Maybe if Ricoh buys that company, first, but even then it would be a mess differentiating between Ricoh, Pentax and Third Brand camera systems.
I think It would be unfair to use legacy mounts as an argument against a new mount. And I think its wise to have a small upgradeability within one mount. Like from APS-C to FF or from 1/2,3" to 1/1,7". I don’t think the current three mounts will remain. K is of course the strongest and will probably last for a long time, but Q are in my opinion a temporarily mount that wont survive the competition from high end compacts the next decade. I wont be surprised if the Q mount is abandoned before 2020. The 645 is another matter. The cameras are good for high end studio shooting but the competition from FF K-mount will be hard. I think it will get an upgrade path to digital FF 645 in the near future to keep its position as a high end camera.
A new mount would probably fill a hole in the current line up and be mirrorless. I have no clue at what sensor format they may choose but I would guess it will offer upgradeability to MF sensor sizes because larger sensors will get cheaper over the next decades and Pentax don’t wont to invest a lot into a short lived mount. It could maybe start with APS-C, FF and 33x44mm but have a large enough mount ring to be upgradable to full frame 645 in the future. Or they may skip APS-C from the beginning. And I believe Pentax will ease our upgrade path by offering mount adapters with electronic coupling and maybe a focus motor.
Originally posted by clackers Your mirrorless camera may have a poor PDAF implementation. Go to a modern DSLR, take pictures (especially in low contrast situations like low light), and see the difference between speeds to focus in Live View and not.
Modern DSLRs are not optimized for non PDAF focusing. The best mirrorless cameras have superior focusing compared to low end dslrs, but they are not quite up to the dslr competition in their own price range. If high end follow focusing is the absolute top priority there is not much that competes with D500, D5 and 1DX mkII.