what happened to my Sonnar?

Hello folks

 

Last night I was shooting and while removing the Sonnar 150 f4 CT*

from my Hassy I noted that the lens shutter fired. This now happens

every time the lens is removed from the body and such lens can not be

mounted again on the camera unless I first turn the sort of red-

marked screw that re-opens the shutter leaves after each shot. I also

seem to notice that the tiny metal pivot (?) which triggers the lens

shutter is a bit looser than the one of other lenses (as soon as I

touch it the lens shutter fires and this is probably why it also

fires when being removed from the body). The camera works fine with

other lenses. Perhaps a spring was broken in my Sonnar? Does that

require a (costy?) specialised repairman or can I do something

myself? Thanks a lot

 

PS: is this a jamming case? but the lens didn't remain locked on the

body..?!?

Ops, forgot to say that despite what happened the lens still works (once the screw has been manually turned and the lens mounted on the camera again).

sounds as if the lock on the shutter-activating axle is stuck or defect. This is a small, spring activated lock mounted on the inner side of the bayonet plate. This lock consist of a hook engaging the shutter-activating axle and preventing it from turning (and releasing the shutter) when lens is unmounted. I have taken it of a few blad-lenses when I had that system, and it's easy to se what is wrong and (if not the rivets is gone) fix it if its sluggish. Important not to get the gear on the inside of the bajonet-plate out of timing(The shutter-activating axle passes co-axial trough this gear and engages the shutter-mechanism). Don't do it if You are not confident in opening the lens - the repair should at any instance not be expensive.

 

Good luck