I use the 40 mm with Olympus 35 sp, the 24 and 90mm on a film or digital Nikon camera, but I sold the 90mm to buy a Leica IIIF...But the voiglander lens wich i prefer it's the 420mm f4.5 heliar for large format, but it's another world...
And i would like to buy the 21mm for my Leica...
But for now no more purchase