The german based engineer " Willi Jensen " is developing a " NEW SLIDE MACHINE " to 4 x5. What do you mean - it is a smal niche - of cause it is - but is it also nice ? If I just could imagine the slide mounts to 4 x 5 inch ? Sure they are with one side on glass - probably with two glasses. The max. I own is Gepe 85mm x 85mm to 6 x7 Slides ! Is it a great coup from your point of viewing ? with regards PS : If the slide mounts will be avaible I sure will buy one package of them - just to have it. Probably I could mount some slides from my 4 x 5 Ektachrome.