Could anybody possible help! I have a Symmar-S 150 lens with a Copal N0.0 shutter which was working fine the other day. Was just about to use it where I noticed the times from 1 to 1/4 sec. are quick, real quick something like 1/250 sec. The times from 1/8 to 1/500 seem to be OK part of the time. When I cock the shutter the lever does not always return to its original position. Only when I let it go suddenly, if I release the cocking lever gently it tends to stay where it is. I suppose a spring or something may be broken inside. Does anybody have an idea what it may be. Is there a repair manuel or something online which could help?