Originally posted by Asahiflex Another interpretation of that bump as I found out on my home forum (pentaxian.nl):
In previous Pentax models the motor for the mirror and the shutter was ALWAYS combined. It's possible that the mirror and the shutter now have their own motor, meaning that the mirror can stay in the up position while taking pictures in live view.
This is not correct.
SInce the k-7 there are separate shutter, mirror and aperture control motors. Thats why you can take shots in live-view without cycling the mirror as well as do DOF preview.
the older k-x etc. series have a single motor, thats why the mirror has to cycle during live view. Much like the nikon d7000/d7100/d600, which cannot do DOF preview without cycling the mirror (very clunky approach). In this regards Pentax has been ahead of Nikon for a long time.