Hi,
I just got a 750mm Apo-Germinar. This huge heavy lens has a particularity that I don't understand. Besides the apperture ring there is another larger ring that can make a quarter of a turn, but nothing changes (seems to change on the ground glass) when you manipulate it. Does any one knows what is this ring for. There is a picture of this lens at http://www.skgrimes.com/lenspics/750zeiss.jpg.
Thanks,
Charles.
Bookmarks