70mm Film Perforations

Hello everyone. I've come across a listing in a magazine for 400 speed 70mm

film that appears to be perforated. I'd all but given up hope for finding 400

that could be loaded into my 70mm (short length) Mamiya film back. My question

is, what is the difference between 473, 480, and 481? I know that 473 is

unperforated 70mm, and I know that I need "type II" perforated 70mm, but I do

not know what 480 and 481 are. Could someone please explain the perforation

differences between the two and which can be used with my Mamiya back? I'm

hoping that it is 480, as that is the perforation that I recently found Portra

400NC available in in 70mm.

Regards,

~Karl

Hi Karl,here's some info; not what you want to hear, but maybe it will help in the future.

According to the 2004 Kodak Pro catalog, film spec 480 is unperforated.

spec 473 = 70 mm, Unperforated, J core, 1 1/4-in. OD.

spec 480 = 70 mm, Unperforated, R-84 spool

spec 481 = 70 mm, type II perforations both edges

Regarding what type I and II actually are, from some "long time ago" Kodak data: there are several different specs; the most obvious is the pitch of sprockets. Type I = 5.944mm pitch, Type II = 4.75mm pitch.

In the front of the catalog, they have a listing of film spec numbers and configurations. From my quick look, only 4 are 70mm film with type II perfs: 475, 481, 488 and 494.

Dear Bill,

Thank you so much for your response. I came upon information about film perfs of

some sort a few years ago on the internet, but could not find the iinformation again with

an internet search, although I'm not very good at searching. Do you know where I could

order a copy of the Kodak pro catalog? I'm doing more and more professional work, and

would love to deal directly with the Big K. Would you or anyone else here happen to know

of a 70mm back (not a 100-ft. model) that accepts unperforated film?

Regards,

~Karl

Karl, I said the perf information was from old Kodak data, but it actually comes from an ANSI standard (presumably also ISO, today). The 70mm type I and II are "...for aerial and related uses."; I presume motion picture film has its own set of standards.

Regarding the catalog, I'm pretty sure it's on their site as a pdf but I don't know where offhand. It's called L-9; if you want to email me, I'll send you the 2004 version; it's about 1 megabyte. FWIW, this is not the master catalog, rather it lists a number of items related to professional use.

I don't think you'll be able to deal directly with Kodak; you'll still need to work through their dealers. But they can special order for you, and having cat numbers may be helpful.