I'm in the process of kicking the tires on an as-yet-hypothetical MF kit I'd kick around with here in the Southern Appalachia's. The P6x7 and P67 are at a much more reasonable price point for me than the 67ii--especially since I'm shooting off a tripod almost always--but I'm concerned whether their relatively "fast" lowest shutter speed is going to trip me up.
A quick pass through my EXIF data from my K5 tells me that when shooting a wide angle lens with a CPL, usually at f/11, my shutter speeds can drop down to near one second when I'm under a heavy canopy and/or shooting in the gloaming. If the rule of thumb is to stop down a couple of stops for MF to maintain comparable DOF, I could see my shutter speeds starting to edge below one second, assuming I did without the CPL on the medium format camera. (I'd also be running into reciprocity issues with, say, Velvia 50, but I'll cross that bridge when I come to it...
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I'm curious if this has been an issue for any of y'all in your shooting and if there's a better solution out there than Bulb mode and "one-Mississippi".