FP4 question to Simon R Galley

Dear Simon,

I used FP4+ in 120 format this evening, after a break of a few years with this film in this format. When I developed it today, I found the base very clear, very transparent. Did you change it recently? It looks like a PET base :/

Dear Aurélien,

From the spec sheet:

"FP4 Plus rollfilm is coated on 0.110mm/4-mil clear
acetate base with an anti-halation backing which
clears during development. It is available in 120
and 220 lengths and is edge numbered 1 to 19
(120) and 1 to 40 (220)."

120 film is always clearer than 35mm because its anti-halation layer washes away and because less is needed from the paper backing. 35mm is always a bit greyer. If you want to know whether it's PET or acetate, just try to tear the film with your hands. If you can, it's acetate. If you can't, after trying real hard and even nicking the film first, then it's PET. Sheet film is usually on PET base (FP4+ in sheet film is).

Sorry if I'm not Simon.

Thanks a lot mhv

Indeed I was really surprised to see a so clear film. I use to work with kodak, foma or bergger films and their base is greyer.

Thanks for your lights

Dear Aurelien,

Acetate base : No change :

Simon. ILFORD photo / HARMAN technology Limited :

Conclusion; FP4+ is coated on acetate because when you tear a little to fast while removing the film from the paperbacking it break up. I only have this when I use Ilford films. The reason I think is the use of a to strong (adhesive) tape. Fuji is doing it much better this way.