Bessa (6x9) F-stop setting arm - which edge to use?

Hi, I have fixed an old Bessa 6x9 folder.

What I'm not sure about is aligning the f-stop selector arm with the

f-stops marked on the shutter body.

Both edges of the f-stop selector arm could have a case made for

their being the edge to use in setting itself against the desired f-

stop marker. One edge is bevelled and one edge has a raised tab,

presumably as a finger anchor but perhaps also as an easily visible

alignment marker. Moving the f-stop to both extremes does not help

either as either edge can be aligned to f22 or f3.5. This is a bit of

a bugger when working with the higher f numbers..in fact I can align

each edge with f22 and f16 at the same time. I just don't know if its

set to f16 or 22 at that position.

 

So after all that waffle...which edge is the correct one to use?

Let me guess: Your camera has a Prontor shutter?

 

I have asked myself the same question.

Read aperture at the beveled edge. The raised tab is, as presumed, a finger anchor.

Start wide open. Move the lever until you see the blades intrude in the barrel, note the relative indices, and stay with that reference. There is room to over-close the blades so a start there is shaky. These things are all about Kentucky windage.

Ah thank you for the replies..I thought I was on auto-update but had no emails so I thought I'd come and check. I also, as ever, did a search before asking...obviously wrong search parameters.

 

Bevelled edge sounds good to me. I'm afraid I can't look at the iris as its currently loaded with a film and the iris is behind the shutter. Would be nice if those findings corroborate with the bevelled edge reading.

 

Prontor shutter? eee? I'm a total newbie with this, all I can say is there is a motif: a circle. inside the circle there are three prongs that radiate to the circle edge from its middle. in the 'spaces' between prongs and circles there are the separate letters A G C.

Patric, by the way what have you found to be the 'best' f-stop for overall sharpness? When I was trying to dial in the focus I sanded down a cd holder to made a ground glass screen (sorta!) and looked at the image through a loupe. I decided f8 and less wasn't really worth trying if sharpness was desired, the center image sharpness seemed to begin to top out f11-f16. The egde image just got better and better the more the lens was stopped down. But f22 was too feint to see if the overall improvement continued into this f-stop inspite of diffusion.

 

I'll eventually find out what a print looks like at f22 and f16, but a sneak preview wouldn't go amiss.