Originally posted by aslyfox It takes any shake reduction system time to spool up. If you are in the habit of stabbing the button, you will see camera shake both because you are inducing that shake with ham handedness, and because the system hasn't been given time to spool.
I just checked my K1, and the SR indicator is illuminated as soon as the viewfinder is active. This is telling me that Pentax has removed the delay that we used to see when the SR had to activate when the shutter button was pressed. I don't know if this is a K1 only thing or if it is common in their other cameras these days.
The trade off seems to be far less battery life, as sensor positioning is a very heavy drain on the battery.
The shake reduction itself has also improved greatly over the past generation or two.