Astrum Foto 100 B&W film ?

I'm trying some of this film now and trying to figure out what's up. I've tried two rolls now exposed at EI 100 - the first developed in HC110b for 9:30, and the second in D76 1+1 for 12:00, and both are essentially clear film except for highlights that would have been overexposed (skies, reflections, etc) if the exposure were correct.

I'm confident in the camera and metering and both rolls were shot in relatively soft overcast daylight so I'm beginning to suspect the "Foto 100" I have is maybe Aviphot 80 rather than Aviphot 200. Or perhaps Tasma?

The undeveloped film is a sort of light blue color on the emulsion side, and the D76 after development comes out a bright-ish yellow looking much like fresh indicator stop. The film base is completely clear. I understand film with this name has been a number of different actual films over the years.

Maybe @MCB18 can shed some light on this?

I'll try a roll at EI25 tomorrow and develop as if it were "RPX25" and see what happens. Was wondering if anyone could recognize it by the emulsion color - i don't know if the various Aviphots look different in room light.

Kind of a neat creepy look shooting right into the sun (deliberately overexposed by quite a bit.)

AnselMortensen said:

Maybe @MCB18 can shed some light on this?

Click to expand...

Yep, I probably can!

@qqphot From my experience, it works well developed 7 minutes in D76 stock, 11.5 in 1+1, and 11 in HC-110B. All of those I got from Massive Dev Chart.

I’d check your chems. HC-110 might be OK, but I think your D-76 might be on the way out if you didn’t get a dense image from that at 12 minutes.

This was a test I did to see if striping the antihal off the film does anything (it doesn’t), the bottom shot is EI 100 without an IR filter developed in D-76 stock.

Anything's possible, but I'm pretty confident in the developer capacity and process, and the same batch of stock developed a roll of Delta 100 (left 35mm roll) unremarkably.

Middle roll here is at EI 100, D76 1+1, 12 min (the HC110b roll looks the same). The fogged edges have substantial density but almost nothing else does except overexposed sky. No filters used.

Rightmost roll (D76 stock 7 min 20C as suggested) is bracketed at EI 25, 50, and 100 - you can see the 50 is just getting past the toe and the 25 is probably pretty usable.

I wonder if the 46mm bulk film that was used for the 127 rolls was from a different supply than the rest of the film from Astrum. Looking at this I feel like it must either be a different film, or very old, but I don't see other signs of age like changes toward the edges, or mottling.

Anyway it's not a big deal, it's always a bit of a gamble. It shoudl be fun to play with it at 25 with a little less development maybe.