Quote Originally Posted by agfarapid View Post
I've routinely shot my Mamiya 645 at 1/30 or higher without a tripod with good results. Of course, a tripod is an insurance against camera shake but if you have a choice of either no picture (because you don't have a tripod with you) or the shot without one, I'd definitely not pass up a good photo op. Heck, I've even hand held my RB with the 90mm 3.8 with excellent results. It seems that the heavier camera provides a steadier platform.
As long as it isn't so heavy your muscles start quivering (which is also affected by how and how long you hold it of course) the heavier camera sure is steadier. Mass is proportional to inertia. Newton lives! This is often overlooked by the fans of the tiniest, lightest cameras possible. I like their convenience as much as anyone but for stability a bit of mass does wonders.