150mm Apo Sironar-s in Pronto professional 01s shutter

[brucep]

I understand that there is some remote control box for this shutter, but using it manually, can someone explain to me what the difference is between the 2 cable release points. One has a white band and the other has a red band.

I assume the little tab on the shutter speed ring is also something to do with the remote control unit.

I just don't want to start playing and cause an expensive repair!

Thanks
Bruce

[Bob Salomon]

One releases the shutter. The other sets the shutter to wide open for focusing or stopped down to shooting aperture.

There are two devices that were available as accessories for the shutters. One is an aperture stick that mounts directly to the shutter and lets you see and select the apertures from behind or in front of the camera. It mounted directly to the shutter. The other was a shutter selector control that mounted directly to the aperture stick and to the tab on the shutter ring.