Originally posted by beachgardener For the K-1, I have read in other threads that there is a major fault with the shutter at some standard speeds creating vibration and consequently images affected with less sharpness. If this is right then they need to publicly acknowledge this and fix this error before any new development of the K-1. And, publicise from serial number xxx??? onward the problem fixed.
I am thankful that further aps-c development is happening.
This can be a problem with any camera and is typically seen in tripod shooting, not when shooting handheld. Typically when on a tripod I use the electronic shutter and that takes care of it. It probably does exist to a lesser extent on APS-C cameras, but is more prone to occur on cameras with larger sensors.
If you want to read more, you can check this link:
Mirror Slap and Shutter Shock – Catching the Light (It isn't something that Pentax is in a deep plot to hide and not something that is unique to their cameras).