enigmatic self-timer

Today I got me a self-timer the working of which I do not fully understand.

I could not find any image of it on the net. The closest resemblance (most probably the same manufacturer) has this one:

http://www.flickr.com/photos/thorpehamlet/6122215666/sizes/l/in/photostream/

Mine is more elongated. It has two markings on the wind-up scale.
They set two different strokes of the release bolt. There are no intermediate strokes.
Intermediate positions on the wind-up scale will only effect the retarding of release.

"G"= 7.5mm

"P" = 15mm


I guess those markings refer to Gauthier and Prontor shutters.

Do they really need different strokes for release? Are these strokes fit?


(There is a thread to adjust how far the bolt runs down into the shutter, but there is no counter-nut and such this Feature is of not much value.)

I mixed up the manufacturers: Gauthier made Prontor and Deckel Compur shutters. So that P and G does not refer to manufacturers.

But Ian Grant thinks it could mean Press and General. As press shutters (self-cocking) shutters need a longer stroke.

Makes sense to me. Thank you, Ian.

another extraordinary release

Bought it yesterday. Made by Bolex.
It is a bulb-setting timer. Once you activate it, it releases the camera shutter but disengages again after a preset time. Useful for the bulb-setting, but actually made for cine cameras.

It also has something remarkable about the release stroke.
As the one above the tapered thread can be fine adjusted in position to the release bolt. In this case though added by a counter-nut, thus practically working.

But it also has a two-step setting. Not by setting a switch as in the timer above, but by adding a second tapered thread. It is a hybrid adapter (male/female) that is screwn on the primary thread. By this the bolt's effective stroke is shortened by 4mm.