Focus screen holder details for Voigtländer Avus 9x12

[SalveSlog]

I have a screen holder for Avus 9x12 with a broken glass. To order a new ground glass, I put some details here that may be of general interest.

The holder and the slot:



Spring pressing the ground glass in the frame. The pin in the middle clears the frame with 2mm:

Max possible width of the ground glass is 92mm:



Top of the holder and bottom, where the slot is:



Slot is 1.5mm:

 

[SalveSlog]

(The reason I was able to put the ruler into the slot at the bottom of the holder, is that some previous owner had broken one edge up. Probably to replace a broken glass plate. He can not have seen the slot at the bottom of the holder.)

 

[JPD]

The groundglass for these Voigtländers has the same size, including thickness, as 9x12 glass plates. You can easily find old glass plates and grind your own GG's. That's what I did. I suspect that was exactly what Voigtländer did as well, bought in the glass meant for plates and ground them at their optical division.

 

[Donald Qualls]

Can't complain about not getting 100% FOV coverage with that method. Might want to clip a couple corners to check coverage if you ever use the front rise/shift that was built into the higher end Avus versions.