Thanks everyone for the informative sharing! I'm getting the synched version of the Packard shutter in the largest size for my 14" lens which is front mounted....that leaves open the possibility of using other lenses. Best, Rich On Feb 11, 2011 8:14 AM, "Chauncey Walden" <clwaldeniii@xxxxxxxxxxx> wrote: I have one that I use on some of my large barrel lenses. I made an adapter to front mount it that will clamp on different diameter lenses to avoid the problem of different lenses having different extensions behind the flange. It has the "instantaneous" pin available if I want 1/25 but my normal exposures with these lenses are much longer. Since you are getting a new one I'm sure the bulb and tube are coming with it, but if anyone needs a good bulb, Harbor Freight has an air blower for a couple of bucks that works great. I use aquarium tubing from a pet store on mine. Chauncey ===================================================================================================...