I'm a relatively inexperienced darkroom person, so forgive me if this is a dumb question. Finally I have my darkroom (aka bathroom) set up again after a shortlived side-trip into the digital world. I ran into a small problem tonight. Up until this time I have only printed from 35mm negatives. I'm now starting to print medium format and so picked up a Rodenstock Rodagon 80mm f5.6 lens a while back on ebay. When I changed lenses on the enlarger, the lens will only mount with the f-stop numbers to the back so I can't see them. My 50mm lens (Componon) mounts okay and also clicks on the f-stops which the Rodagon doesn't. Am I doing something wrong? My enlarger is a Saunder/LPL D6700 if that helps. I won't be home tomorrow but I'll check in tomorrow night to see if anyone has any advice. Thanks in advance.