Quote Originally Posted by andrewch59 View Post
Thom, I was wondering what shutter you use with the congo? Seems the large copal 3 shutter I purchased for this lens does not fit (too small), I have no other options
You may have a Copal 3S shutter, not the Copal 3 that the Commercial Congo 360mm f/6.8 lens needs. Confusingly, some 3S shutters are marked 3. The 3S has 56mm threads, the 3 has 58mm threads.

Kumar