Quote Originally Posted by thuggins View Post
I've wonder this myself over the the years, and here is my thought process.
1) Standard lens for 35mm format is 43mm, for MF it is 85mm. That is essentially one stop when it comes to hand holding. Moderate telephotos become impractical.
There is no general 1/focal length shutter speed rule. It's just a good rule of thumb for 35mm format. Actually the necessary speed is related to the angle of view. Of course I admit there are other reasons why you'd probably prefer a little faster shutter speed for medium or large format. On the other hand with larger negative you can use faster film without compromising the IQ too much.