Shooting Expired Konica Infrared 750nm Film

This past week I obtained a box of used film from a coworker for a song. He told me it had all been kept in cold storage until about a year ago when his wife wanted to reclaim freezer space. Among various kinds of 120 and 35mm film, there are 18+ rolls of expired Konica Infrared 120 film. I haven't checked them all, but it appears they expired about 20 years ago.

My plan is to shoot a test roll using my Bronica SQ. I have a 25A red filter I'd like to use with it. (I know darker filters would be ideal, but that's what I have to work with.) I've found various suggestions for shooting and developing this film, but I thought I'd ask here in the hopes someone is familiar with this film.

So my basic questions are: (1) Any suggestions on how to expose this expired film? (2) Any suggestions on developing it using D76? I can't really afford to buy some exotic developer to try, so I'd like to use what I have.

Thanks!

digitaltruthphoto.com and take a look at the massive development chart under discontinued films, the times for d76 should be there. This film keeps really well for infrared. You'll likely have a little bit of base fog, I have sold a ton of this stuff recently that was that old and haven't had any complaints. 1/4 @16 with the 89b filter that I use or 1/60 @5.6 with a red 29 if i remember correctly.

With Konica IR you ca use 25A red filter with good success. I used Konica IR years ago, too bad they don't it anymore, I really like it. Last time I used it, I used 1/60 at 5.6 with the 25A Red on the camera. Of course being 20 years old, I don't know whats going to happen.

Jeff

Thanks, guys. I think I'll try the f/5.6 @ 1/60th with my 25A filter as a starting point and see what I get, as well as consulting the massive dev chart. I figured somewhere around 6-7 minutes in D76 full stock would be about right. Can't wait to try it out!

I have some too. I think I rated it at EI 3 to 6 with an 89b (opaque). Sounds like you have enough to maybe nail down an exposure and have some fun on the cheap.

If I think about it tonight, I will look up what little notes I kept and report.

Thanks, Rich. If you uncover anything interesting I'd be happy to hear what you've got.

Yes, I shot one roll bracketed at EI 3/4/5/6. D-76 neat for 9 minutes (for no other reason than that's what I used for HIE). I have four rolls left.

Maybe not a bad starting point, but like was suggested compare to the massive chart. And no telling how it has aged. And the IR present.

Thanks for the info, Rich. I went ahead and developed for 9 minutes in D-76, as you suggested. I found a tech sheet online from Konica and followed it on agitation: 1 minute continuous and then 8 minutes agitating every minute. From a development standpoint, the results seem good. I will say that the two rolls I shot came out exceptionally dark, so I think I'm going to shoot the next roll opened up 1 stop. (I used the recommended f/5.6 @ 1/60.)

The only major hurdle left to overcome is the horrendous curl in the film. I cut the first roll and sleeved it in a PrintFile sheet - it's basically unscannable on my flatbed as it won't stay remotely flat even in my film holder. That's now under a heavy stack of stuff. I left the other roll hanging as it dried, with a weighted clip. If it's still badly curled tonight, I may try reverse rolling it back onto the spool overnight.

I found one roll of this at a flea market that expired in 1992. If I remember correctly, I treated it as ASA 32. I used a red filter as I don't have an IR filter, so I added another three stops or so for that which put me around ASA 4. I developed it in Rodinal 1+50 for about 5:00 at 68F. It came out a little grainy, but I'm happy with what I got. Here's the result:

http://www.flickr.com/photos/rjbuzzclick/6257612282/