Topic: Where to start with unknown expired film?

[rotarysmp]

I just bought 5 rolls of Agfa T605B.

Never heard of it before. Internet searches bring up nothing at all. I dont even know if it is a B&W or a color film. Slide or negative. If this purchase only nets 5 daylight spools, and cans I can use to break down a 400' roll, I am happy with that.
 I would like to take a shot at using the film. How do you approach this?

Is this a good approach?
- Load a film, shoot a number of clips in daylight at EI 5, 10, 20, 40, 80, 160, 320. Stand develop it in Caffenol C-L.
- If images appear at all, based on the emulsion color, maybe do a second test in C-41.

What do you think?
Mark

[Kai-san]

First of all, have you got a camera that takes 16mm film? The box states 16mm Gevachrome High speed, which means it's 16mm slide film. See if you can find any ISO / ASA rating on the box or the metal tin. Is there an expiry date anywhere?

[Francois]

Since it's German film, you will probably find a DIN speed rating.
There are conversion charts between this and ASA.

The T in the name suggests that it's probably a tungsten balanced film.

[Bryan]

It's a color reversal film like Kai said, 320 ASA if I'm translating that correctly.  I would bracket like you said but I wouldn't expect very good results with Caffenol. 

https://filmcolors.org/wp-content/uploads/2013/09/Rens_vanBets1968Gevachr6.00.pdf

[Kai-san]

I've shot a lot of Tungsten films in daylight using 81A/B/C filters with very good results, but if these films are way over their expiry dates and have not been stored cold there might be problems. The expired reversal films I've shot at box speed have all got washed out colours and are overexposed. Is it possible to counter this by shooting them at lower ISO?

[Francois]

Slide film usually likes to be underexposed. Shooting them at a lower ISO would increase the exposure even more.
But this is expired stock...

What throws me a curve ball right now is the reversal bath... it messes a bit with my brain.
So, lets go from start...
Slide film has a characteristic H&D curve in the shape of a mirror S. (the opposite of negative film)
Like all films, age adds a layer of base fog at the bottom, so the highlights will suffer. (inverted curve)
Since you end-up with a more limited dynamic range, pulling the exposure a bit should move the highlights into the mids. The film will appear darker but the colors will be better...
Pushing development a tiny bit probably would help.

Does that make any sense or is it just me who can't seem to figure this one out?

[rotarysmp]

Thanks a lot everyone. That is a lot of good advice and info.

I missed the xxxchrome in the name. Duh!

I have a 16mm Beaulieu R16 camera. I think I'll try C-41 cross processing this stuff, as I have no real interest in trying E6. I will be scanning the results. That might also return some of the lost contrast. 320ASA is a pretty decent speed. Even if it has lost a stop or two (or 4 in the 40+ years since it was made), there might be potential for artificial light usage. As I said, I will be happy to have a set of spools and cans from this purchase.

I'll keep you posted on the results once I try it.

[rotarysmp]

Thanks for the Data sheet Bryan. So it is a 160 ASA film. That gives me a starting point.

[Kai-san]

Slide film usually likes to be underexposed. Shooting them at a lower ISO would increase the exposure even more.
But this is expired stock...

What throws me a curve ball right now is the reversal bath... it messes a bit with my brain.
So, lets go from start...
Slide film has a characteristic H&D curve in the shape of a mirror S. (the opposite of negative film)
Like all films, age adds a layer of base fog at the bottom, so the highlights will suffer. (inverted curve)
Since you end-up with a more limited dynamic range, pulling the exposure a bit should move the highlights into the mids. The film will appear darker but the colors will be better...
Pushing development a tiny bit probably would help.

Does that make any sense or is it just me who can't seem to figure this one out?

I think you're probably right. I get confused as well by the fact that it is a positive image, but the reversal process is in the development process, not in the film. It will be interesting to see what Mark can achieve with C-41 processing.

[Francois]

I'm doing the thinking like that for two reasons:
-Companies do the density calculations based on properly developed film using the prescribed process (well, duh!)
-When cross processing, the H&D curve doesn't just flip; so I have no ways to know what it would be like in the real world.

I suspect that it will become steeper (higher contrast), but I really can't tell without testing with a densitometer.

[Pete_R]

I have no real interest in trying E6.

If you read through the processing instructions Bryan linked to, it looks more like an E3 process with a second exposure to cause the reversal rather than a chemical reversal which was introduced with E4.

[rotarysmp]

I also thought when I read that, that it is a earlier process. I'll get some C-41 and see what comes out with it. This film came out before 1968, so the ones I bought are probably about 50+ years old. I have no strong expectations on these. If I can get a couple of useful clips on rolls from these, it is a bonus on my expectation of only getting daylight spools and cans.

There is also some Eastman 7248 EXR 100T available, listed as "always stored cool" (whatever that means, Kodak recommends freezing below -14°C for long term storage). That film will be between 20-30 years old. What are you experiences with exposed film. Worth the risk. or a waste of time?

[Francois]

Developing film that was exposed a long time ago is always a big gamble, especially when it comes down to color.
Personally, every time I tried to develop stuff that was stored at room temperature, it simply failed

[rotarysmp]

I wish Orwo would hurry up and release the next batch of UN54. That would make things a lot simpler for learning 16mm.

[Francois]

Definitely.
While I'm not picky when it comes to B&W and have had success with some long expired films, color is always a whole other ball game.

[rotarysmp]

I ran two test development attempts.  Turns out this film has a Remjet layer (I missed that on the data sheet). If comes off pretty easily when wet. The fixer test shows a slightly milky yellow base material.

The film was rated at 160 ASA at production, according to the data sheet.
Bracketed at ISO 400, 200, 100, 50, 25 and then closed the iris, and shot some feet without further exposure.

Darkroom opened the camera, cut the film, and I did a "bucket development" just stuffing the film into my JoBo tank with no reels, but with the center tube installed which is part of the light trap.

First attempt: 70 min stand development in Caffenol C-L for 70 minute and 20°C. Stand dev is not ideal for an old fogged film, but I figured it might give me an idea of the remaining film speed.
Result--> Black film, nothing visible. No clear bits anywhere.

Second attempt: same bracketing, also a clear bit. Developed in Parodinal 1+25 for 12 min at 20°C.
Result--> Black film, nothing visible. No clear bits at all.

Unless I am missing something, this film is fogged to completion. Unless you have a suggestion of another test I am missing, I don't see much point risking €100 for a C-41 kit to try and get an image on it.

Guess I'll wait for a 400' roll of Double-X, (just missed out on one on German classifieds yesterday), and use the Geveart reels and cans to break it down to 100' loads.

[Francois]

It's probably cooked beyond saving.
I could suggest using some benzotriazole as an anti-fogging agent, but that won't have any effect on the color part of the emulsion.
Years ago I tried salvaging the pictures from an old roll of Kodacolor in 620 format, but essentially got a black film with nothing on it.

Old color film is really one of those finicky beasts...

[rotarysmp]

Thanks Francois. Oh well. Not the worst "investment" I even made