LF lens has strange nub.

[Wayne Crider]

My 90mm Graflex Optar has a round protrusion on the back, 3mm in diameter by 3mm high, that won't allow the retaining ring to tighten the lens to a metal lensbo ard. As it is I would have to drill or file a slot for the nub to seat the lens flat to the board. But it still won't allow the retaining ring to tighten down. Did they use spacers for this lens?

[M.]

There was a matching slot in the lens board to assure that the shutter was seated so the shutter release would just touch the little dojigger connected to the body release.

[Sean Billy Bob Boy yates]

yeah, Large Format can be so technical, eh Dr, Mitch?

[E.L.]

I always thought the little screw was to keep the whole shutter from turning when you wind it. I have had to take the screw out on some mounts. Original boards had a small hole for it. It seems like even new shutters have them.