Recently a friend of mine made an adapter for me that enables me to fit my "old" Mamiya 645 medium format lenses on my "modern" ST-8300M CCD-camera. Because of the large flange focal distance of the Mamiya 645 lenses, there remains enough space to fit a filter wheel between the lens and the camera.
On the evening of January 31, 2012, I've tried out the adapter and it works! The adapter has been made a little shorter than calculated to be sure that the lenses can be focused in combination with filters in the light path. Instead of rotating the lens to the infinity mark, the lens has to be focused on a bright star (or object on the horizon).
First light was with a 45 mm f/2.8 lens and 7 nm H-alpha filter. The camera and lens were mounted on my Vixen Photoguider.
I took 12 images of 5 minutes each (unguided and rough polar alignment). Two images were wasted due to guiding errors, so here is 50 minutes of Barnard's Loop in Sweet Lake City's light pollution soup.