Originally Posted by 2F/2F
my bracketing proposition was meant for only one film. Just to have an idea of what a reasonable EI is. That procedure would reveal quite a lot. If Jim wants to fine tune, then he can spend one more film with limited bracketing this time. Something like 3 exposures per scene. After that, he will still have 13 rolls. Not bad.
Turns out I have ten rolls, not 15, but the logic still applies.
Jim MacKenzie - Regina, Saskatchewan, Canada
A bunch of Nikons; Feds, Zorkis and a Kiev; Pentax 67-II (inherited from my deceased father-in-law); Bronica SQ-A; and a nice Shen Hao 4x5 field camera with 3 decent lenses that needs to be taken outside more. Oh, and as of mid-2012, one of those bodies we don't talk about here.
Favourite film: do I need to pick only one?
Well, I just did a speed test with my newly acquired 2475 Recording 4x5 sheet film that expired in 1967. Storage unknown. I developed 9 minutes in HC-110 dilution B at 68F, using the Nikor sheet film tank. I shot sheets at EI 800, 400, 200, and 100, and put in one fogged sheet, and one unexposed sheet.
The background fog is serious, film base plus fog is a density of 1.06. The Dmax of the fogged-out sheet was 2. That's a reasonable Dmax, but longer development might increase the fog more than I would gain in density for highlights. Plus, higher Dmax makes it less scannable, this film isn't going to be printed optically. So I will stick with 9 minutes.
As for the film speed, even EI 100 is really not quite enough. Of course, it has 4 stops of fog, so that's no surprise on a film that was originally ASA 1000. I think I can safely go out and shoot this stuff at EI 50, and have tolerable shadow detail.
Grain is the classic 2475 grain -- although in large format that's not so serious.
The film base on this stuff is 0.004 Estar (polyester), which is unusually thin for sheet film. It's somewhat curly right out of the box, a trick to get into the film sheaths. (My 4x5 is a Pony Premo #4 using plate holders with Kodak film sheaths.) Once processed, they roll into 1" diameter sausages when dry -- even more annoying than 2475 Recording in 35mm size! I have no idea why they made it on such a thin base, maybe it was a special order and they cut up a master roll made for 35mm film. Kodak certainly had Estar Thick Base by 1967, that would have stayed flat.
At any rate, it's pretty crazy, 40 year old film in a roughly 100 year old camera. But, heck, if I can make this stuff work, the Delta 3200 can be made to work, at least somewhat.
Last edited by John Shriver; 01-10-2009 at 07:33 PM. Click to view previous post history.