This is just a short note to express how troublesome things like "shutter shock" are. We have the expectation that the march of progress would have freed us from things as trivial as shutter blade inertia. After all, that is what shutter shock at "slow" shutter speeds is...the resonating tremor caused by a few hundred milligrams of metal accelerating/decelerating before/after a short trip across the frame. One would think that the state of the art should have progressed a bit since the late-1980s.
Sadly, increased quality of long lenses coupled with high sensor resolution allows us to see what has been with us for years. Almost as sad is that our camera support (tripods + heads) sometimes contribute to the problem with kickback resonance from the first curtain braking action. Going down the list, with the tripod out of the picture we have subtle interactions between user technique, Pentax SR, and camera initiated vibration. I am discovering that I can no longer shoot hand-held with a heavy 200mm lens.
Lastly, not all vibration comes from the camera, even if paired to a competent tripod. Wind is an ever-present foe as are the temblors from traffic.
Conventional wisdom:- Expect greater impact from all causes at slower shutter speeds
- Dampen with extra mass
- Avoid creating levers with gear. This includes suspended mass acting as a pendulum.
- Be aware that when the wind blows, the tripod hums a tune
- Tripod resonance is real. Tap the leg and feel the response on the prism housing.
- It is terribly hard to be perfectly smooth when releasing the shutter
- For the most part, any camera support is better than none
One might add that stability is often an exercise in compromise. Consider the setup below in light of #3 in the list above.
Steve