Hello, Zach - and the others, e.g. film4eva - et.al.;
my name is Jan-Peter from Southern Germany - and first of all I want to thank you very much for this thread! - Here I want to give my report on the 70-mm-experience:
In summer 1985, long time ago, I got my Hasselblad 500 C/M brand new with the Planar CF-80mm, the Distagon CF-50mm, the Sonnar CF-150mm and three A.12 magazins/backs. - By the time I added up with the legendary Distagon CF-50mm und the Tessar CF-350mm, as well as several other back, such as A.16 and A.24.
Two years ago, in autumn/fall 2022 I fnally got hold of my first A.70 back from a daughter of someone who gave up analogue photography that would include 7 cartridges filled with very oulde Plus-X-70mm-film. - I had this A.70 back serviced by Peter Gierens a very nice guy near Cologne in Germany who has good knowledge and is trading real fair.
Now I had to develop these films. I took two Paterson spirals, vice-versa, to fit the 70mm distance between them and had the usual go with Ilford ID-11, 1+3, 22°C an approx. 16 mins. They came out real well though with a fairly darkened mask. - However this method need a good patience to feed the reels, though I never had the problem that parts of the film would stick together during the processing, no wheeling, but "shaking" the tanks. - The disadvantage of using the usual Paterson reels is that you have to cut a full lenght film of approx. 5 mtrs twice meaning that you lose two prints and wich you cannot really predict what prints these will be - though obiously they will not be on the end or beginning or in the middle of a 5 mtrs-lenght 70mm-film.
After drying these 70mm-films with pegs in front of a window leaving them for maybe three or four hours I cut them in 3-prints lenghts and put them in these usual pergamin sleeves or "pages" DIN-4-sized. They just fit in there.
Of course I wanted to enlarge the negatives. - I have two Durst BW-605 enlargers, one at our home at LAke Constance, the other in our second home on Italian Lake Como, actually Lago Mezzola, VAl CHiavenna - and also a Durst Laborator 138. - I got hold of another/second negative carrier for the Durst 605 and took out the format holders for 35mm and 120 negatives - thus I can freely move the 70mm-film in the carrier and can enlarge prints nearly any size - actually I enlarge small sizes for the album - and 12x12" and 20x20" sizes for framing - and it works really well.
Enlarging with the Durst Laborator 138 is a lot more comfortable with large sizes - however I have no solution for the "extra-wide" 70mm; I think I will get an extra Lapfe mask probably from someone who can do these on a 3D-printer.
As I did proceed really well I bought some of the large 85 mtrs. rolls of the Agfa Aviphot 200, perforated, from this seller in India - and have very good results in Ilford ID-11, 1+3, 22°C and 22 mins - or also 20°C and 28 mins. - The big advantage of this Aviphot that it has an enlarged range for infrared photography! -Thus you can take a photo as a usual b&w photo as well as an infrared photo.
However for this moment I have two questions: (a) Recently I got hold of four 45 mtrs rolls of this Aviphot 200 films which is obviously un-perforated. - When I use my standard Hasselblad A.70 back I can frankly use it as well however would not have the counter to run along - or won't it work at all? - (b) If I simply may directly ask: Is this Mercuy Murnau 100 70-mm film the same as the Rollei Retro 80S - just changing the name - or is this Murnau film a newly or freshly coated emulsion on a film basis? - I know the Rollei Retro 80S fairly well and have entirely no objections.
Item: I would join everyone in using 70mm film indeed - and want to thank Zach very much indeed for this wonderful encouraging and informative thread - and his website!!
Jan-Peter