Originally posted by causey A very relative notion of "no shaking"... There is always some, perhaps imperceptible, shaking when shooting hand held.
So, regardless the brand, there will always be a shaking issue, hand held or not.
Even on a tripod, any camera will be submitted to a certain, inevitable, shaking due to the system of the shutter, wether the mirror is locked up or not. So don't criticize (bash) Pentax alone.
And, if I understood some comments correctly, the larger mass of the camera might perhaps reduce the consequences of that 'shaking'. Then, who knows, mounting the battery grip could help till a certain extend, because this adds a mass to the camera body.
As usual, correct me if I am wrong...
BTW, a central shutter, as in the lenses of my MF (or LF-) camera, could be the answer. Once the mirror is locked up and the vibrations are faded away, the only, tiny, things moving are the thin leafs of the in-lens-shutter.