Originally posted by Digitalis Compared to the flange from the Canon and Nikon systems it is only a few mm longer. If that fact disturbs you, perhaps a DSLR was the wrong choice for you.
I thought I made myself clear. I have no doubt that DSLRs themselves are dying. The reason why SLRs were invented was so that you can see exactly what you are going to shoot, the most complete and perfect preview that was technically possible at that time (apart from twin lens reflex cameras, but those were bulky, expensive (2 lenses!), ...). That's why they went through the trouble of using that mirror. Later it proved useful in order to get good auto focus. But nowadays you get an even better preview (in some aspects, soon in others too) by skipping the mirror. Technology has simply advanced. The mirror is simply not needed anymore... at least if we look, say, 5 years into the future (the way things are going). Pentax will drop the mirror too, eventually. The question is how far are they willing to go, and _I_ hope that they will go all the way and create a new mount and lenses... which should be absolute state of the art, be as good as Pentax can make them. I know it sucks for legacy users (including me), that is why they must make the transition period as smooth and painfree as possible. IMHO the solution is to provide a lens mount that does not sacrifice anything, that makes it possible to use the old lenses as good as they would have worked had Pentax made a K-mount mirrorless.
As for larger sensors... what for, really? Smaller sensors are getting better and better, too. My smartphone, with a 1/3" sensor, these days can compete with my old Pentax DSLR, and by far exceeds it in terms of sharpness when there is enough light. I like APS-C as a sensor size, it's not too big, not too small, you get a nice shallow DoF without struggling too much when you want to have more in focus. It's also very close to Super 35mm. mFT isn't doomed because they can go full frame.