Hi !
I have the same problem with my Opemus Standart.
I was lucky to find a flat ring at eBay. Now I can
make prints up to 8 x 10. For bigger prints you'll
still need the "right" lens mount which goes dipper
in enlarger body.. Try to contact Meopta directly -
they have a lot of spare parts for their older enlargers.
Or just use another lens..
Best wishes,

--
Igor
http://www.arrakis.es/~igapop

escribió en el mensaje
oups.com...
I've recently aquired an Opemus 3 (Meopta) enlarger.However my
enlarging lens is an f2.8 Nikkor 50mm.Its thicker(wider) than the f4
Nikkor and will not fit into the lens mount (it has to be in the
inverted position or it will not focus).Is there a lens mount (eg.flat
type) that will accommodate my 2.8.Thanks for any suggestions coz i
need to start work!