So, I got to thinking today...
I know, I know, a rare occasion! LOL
My question has to do with flash sync speed limitations.....
The Schneider LS lenses I used with the 645DF body had a maximum flash sync speed of 1/1600s. The RZ67ProII has a maximum flash sync speed of 1/400s. These flash sync speeds are based on the use of leaf shutter lenses of course.
Canon and Nikon get around this with their focal plane shutters by pulsing their speedlites to simulate constant light during the shutter duration, albeit at greatly reduced power. I have used the Canon flash system routinely up to 1/8000s (high speed sync). I have ganged speedlites together to create an array that produces the appropriate light output needed, while also syncing at those speeds. I have even played with Profoto studio strobes wirelessly syncing at 1/8000s using the Radiopopper Jrx system (too much explanation to go into here).
My question, however, pertains to leaf shutters specifically....
What is the limiting factor in terms of flash sync speeds? I surmise it is the mechanical ability of the shutter blades to open and close reliably. Furthermore, I assume this is due to the weight of them, and the springs used to perform the work of opening and closing them. Schneider achieved it up to 1/1600s with the 645 lenses. Mamiya achieved it up to 1/400s with the RZ lenses. The Schneider lenses must use very light materials as well as being physically smaller than the RZ lens shutter blades.
Having said this, wouldn't stiffer springs and lighter carbon fiber or titanium blades allow greater sync speeds?
If anyone has any insight here, I would love to hear the theory. Besides being a photographer, I have a Masters degree in structural engineering.