I have just got myself a Meopta Opematus 6x6 enlarger. The unit itself seem to be very good quality and even have auto focus (rail). The Opematus comes with an uncoated 4/75mm Belar lens, think it is tessar type. SO I have two questions: 1, Will the autofocus work with a 50mm lens, I am eager to do some large 35mm prints. There is a find adjustment, but I don;t think it will compress the bellows enough to allow a 50mm lens to focus properly. Anyone with experience? 2, What are the names to look for if I want t get myself a 50mm lens? I know about Belar and Anaret, but the 23,5mm thread seems to be rather difficult to find. I know there is a converter, costs about 6eur, but I think it will add more displacement and makes using 75mm and shorter difficult.