Tetenal C-41, coloured spots on film..???

Drikusniet: Thanks for asking. Yes, you are right in your observation: the first time fresh chemicals was used I had no problem, next time a few flakes and than more and more. The bottles I have used has not been used for other chemicals, as far as I know I started using them for C-41 the first C-41 set of runs I did more than 2 years ago, without any problems (Fuji film that time); and since then I haven't done any C-41 until now with Ektar 100, but haven't mixed the bottles or used them for anything else, each bottle for each chemical and the same for other other equipments used for each chemical.
The company who sold me the stuff is just about to discuss the matter with Tetenal and Kodak, and I'm waiting for what they have to say.
But since the last time I commented on this thread I have started to suspect that something is wrong with the last stage of the process, the stabilizing bath. I have several times filtered the developer and the bleach fix, but as far as I remember, only once the stabilizer bath. When I now did that some days ago, when sending the stuff to the company, I did find "flakes" quite similar to the thing on the film in the filter paper! I don't really know what the stabilizer contain and what it is supposed to do, but Tetenal says that "the stabilzing process may also be carried out days later". I now have one more exposed Ektar 120 film which I will develop within some days and which I will develop, wash and dry but not stabilize before I see what I have. (Last time the sheets looked very smooth and nice when I took them out of the wash, but not as smooth and nice when taking them from the stabilizing bath - but I wasn't careful enough to be really confident with this observation of mine.)
/Bertil

Bertil,

PhotoEngineer has commented on the chemical properties of stabilizer several times, and from what I read it doesn't contain any critical chemicals which could possibly produce those flakes.

One thing did come to my mind, though: before you stabilize, you perform an extensive wash. Could it be that the wash introduces these flakes somehow? I could imagine that the flakes build up in the stabilizer only as some of the flakes introduced during the wash end up there. And since the stabilizer is the last step, film after film it is less and less able to wash away these flakes as it accumulates more and more of them itself.

Just my 2 euro cents ...

I have now performed "my last experiment" concerning Tetenal C-41and Kodak Ektar 100, i.e. I have in this case developed one (1) 120 film Ektar 100 in the same Tetenal C-41discussed above: i.e. Jobo CPE-2,Tank 2553, developing temperature 38°C . (100°F), rotating speed 2 (fast). Washing in something like 36°C after developing and beach fix, the film has put in a bath with some drops and Kodak Fhoto-Flo, (some drops of Kodak Photo-Flo also in water used in bath for 2 minutes before starting the developer) and hanged to dry:

Result: NOT A SINGLE SIGN OF THESE FLAKS!!!!.

I have now put this dry and clean film into the stabilizer bath (roughly 20°C) which today was filtered.
Tomorrow we will see if something has happened. But in any case: no "flakes" on the film, dry and clean, before the stabilizing bath!!!
/Bertil

No doubt this "flake problem" enters the process with the stabilizing bath, the filtered stabilizer left no "flakes" on this Ektar film after stabilizing and drying, but after filtering the bath the filter paper contained a lot of these glimmering flakes! And these flakes are not only related to the Ektar film. I have now successively developed 3 rolls, 120, of Fuji Reala, each time the film was hanged to dry before stabilizing and showing no trace of these flakes, before stabilizing. By filtering the stabilizer after each film I managed to avoid any problem to the stabilized film, but "flakes" no doubt was visible in the filter paper ... but less of them after each processed film (well, on film # 2 that was stabilized without having filtered the bath after #1 did show one piece of flake (!) that at least I hadn't discovered on the dry film before stabilizing it!).
Last time I developed 1 Reala and 1 Ektar and stabilized them immediately after washing in a newly filtered bath, and everything came out nice and clean; but after filtering the stabilizer bath I couldn't even find any trace of these flakes in the filter paper this time!! Perhaps my stabilizing bath is getting a little bit tired now, after all, it's film # 10 and 11 that this chemicals have been used to process.

I agree, Rudeofus, having tried to look into what the modern stabilizing bath is supposed to contain it's not easy to understand how these flakes are produced – but I can't come to any other conclusion than that they belong to the stabilizing bath, since no "flake problem" if I skip this last part of the process. Unfortunately, haven't yet heard anything from Tetenal (material and description have been sent to them) about some kind of explanation of this "flake" phenomenon: is it this particular batch of chemistry or my water, or my bottles, or my ...???
Anyway, I seem to be able to handle the "flakes" by always using a newly filtered stabilizing bath.
/Bertil

Bertil,

you observations and conclusions sound pretty convincing, something is rotten in the state of stabilizer Since Photo Engineer posted the recipe for stab and it contains only easy to get chemicals, you could mix some home brew stabilizer and check whether this home brew produces the same flakes or not. If you still get those flakes, one of your previous process steps seems to mistreat the film so that is disintegrates in the stabilizer, if you get no flakes (more likely from what I read), I'd say it's time to confront Tetenal with this. I have successfully communicated with Tetenal several times, it can take a while to get their first response, but after that they are usually quick and helpful.

Good luck with your experiments!

I agree Rudeofus "something is rotten in the state of stabilizer"!
According to Tetenals homsite, the C-41 stabilizer should contain something like:
Alcohols, C12-15, ethoxylated
Hexametylentetramin
1,2-benzisotiazol-3(2H)-on
Unfortunately, my knowledge in chemestry is not enough to have an opinion on the matter; the only thing I can have made wrong, as far as I can see, is my water, though "my water" is supposed to be the best tasting water in the north of Sweden, BUT tasting good in not the same as "good water for C-41".
Sounds nice that Tetenal is communicative even if it take some time. I will let you hear what they have to say. Waiting for their response I will do some B/W work!
/Bertil

Bertil said:

Unfortunately, my knowledge in chemestry is not enough to have an opinion on the matter; the only thing I can have made wrong, as far as I can see, is my water, though "my water" is supposed to be the best tasting water in the north of Sweden, BUT tasting good in not the same as "good water for C-41".

Click to expand...

I can't exactly claim to know what these chemicals are supposed to do, but your remark with the water rang a bell: you are aware that there should be absolutely no wash step after the stabilizer. For this reason I always use deionized water for mixing the stabilizer bath to make sure that I don't end up with water residues on my film after drying. It would be interesting to measure the pH value of your stabilizer bath before and after stabilizing a roll of film.

Long time ago!!
Never got any comment, any explanation, from Tetenal, gave up!
Anyhow, when I started to filter the stabilizer after each run (ordinary coffee filter!), or before a new run, I have no problems of the kind that started this thread. Very Good – end of story!

Quite another thing: some time ago I had another problem with C-41, my Jobo CPE-2, running with tank 2553 and 120-film at 38° C (100°F) at 3'15", and at the fast speed #2. No doubt the edges of the 120 film was, compared to the center, overdeveloped – thus uneven development (hate that kind of shit).
Now, still using Tetanal C-41, I run at the other recommended temperature, 30°C (86°F) at 8 min, with the lower speed, #1, and each minute I loosen the tank and agitate the ordinary way for some minutes, up and down and so fort. In my judgment the result is quite OK perhaps even good! (well, I don't make analog prints from my negs, just scan and print the digital way – have never liked colour prints, save some "dye-transfer prints" by among others Irving Penn!!

Best regards

/Bertil

Recent experiences in the land of Tetenal C-41 stabilizing bath:

New 1 liter Tetenal C-41 kit. Stabilizing bath made with deionized water. Developed 5 120-rolls without problems: no "flakes"! Filtered the stabilizer and run 6 more rolls. The first 3 rolls no "flakes", small amounts of these "flakes" on the roll 4, 5 and 6, more on 6 than 5 than 4!! Developed yesterday 6 Ektar 4x5 sheets. Stabilzing bath filtered: some small "flakes"on the last stabilized sheets!
Obviously: when the stabilizing bath is really fresh no broblem with at least stabilizing 5 rolls 120 film. When used this "flake-problem" start happening unless filtered after just some use.

Why am I the only one with his problem, I process the rolls as everybody else! ???? I think!

/Bertil

PS. No problems anymore with overdevelopment of the edges following the agitation method above. DS

You're not the only one, I have seen many reports of Tetenal "stabilizer" causing problems. I think they changed it somewhere in 2008-2009. I used Tetenal then and the stabilizer suddenly changed from a clear, formalin-smelling liquid to a brownish mess. But I switched to Fujihunt kit then.

Tetenal and Rollei are just con artist companies selling crap that somehow barely works or may not work. They just have good marketing so it is easy to buy their products anywhere. It's a bit sad; good products (such as FujiHunt) are hard to come by and AG Photographic in UK is one of the very few who sell them.

Many thank for your reply, hrst!
Don't feel that lonely anymore!!
Yes, Tetenal is easy to get, and for a nice price (at Impex Berlin among others), but would be more easy with a better stabilizing bath! My stab. is a clean non-smelling stuff, but something is wrong with it.
Thanks for the FujiHunt hint at AG in UK.
Best Regards
Bertil

So, the key seems to be make your own stabilizer?

Yes Tony, but how?
/Bertil

Just adding formalin to a Photo Flo / Ilfotol / Agepon / etc. solution (prepared as instructed or to your taste) should be an appropriate old-style stabilizer which should work fine for both old and new films.

Search for posts from Photo Engineer on the subject to find how much. I think it is something around 5 ml/l of 37 % formalin solution.

Many thanks hrst for your reply.
Found the conversation below about stabilzer, you seem to remember quite well. Though modern C-41 films don't really need formalin it doesn't seem to make any a problem using "old-style" stabilizer, at least PE doesn't advice against it's use in modern C-41 films. This conversation ends with:

"Photo Engineer
04-13-2012, 11:35 PM
I am preparing a lengthy and hopefully definitive post on stabilizers. I am working on it.
PE",
but that definitive post is not yet on line as far as I can see.

/Bertil


nworth
04-12-2012, 04:45 PM
As you can see below, the positive and negative stabilizers are nearly the same. The negative (C-41) one has a bit more formaldehyde.

Kodak S-16 stabilizer
Used in Process VNF-1 for Ektachrome color reversal motion picture film
Water (21 – 27C) 800 ml
Kodak Stabilizer Additive 0.14ml
Formaldehyde (37%) 3.5 ml
Water to make 1 l
Treat film for 30 seconds at 35C.
Note: Kodak stabilizer additive contains polyethylene 12 tridecyl alcohol.

Not quite the same as E-6 stabilizer, but close.

C-41 stabilizer
This was listed as the “semi-official” formula for the Kodak C-41 process
Water 800 ml
Formaldehyde (38%) 5 ml
Kodak MX812 0.8 ml (wetting agent)
Water to make 1 l
Ref: Dignan Photographic Newsletter, July 1974
------------------
Photo Engineer
04-12-2012, 05:11 PM
The stabilizing additive and wetting agents are virtually identical and are equivalent to Photo Flo 200.

In E6 films and in older C41 films, the Formalin served two purposes. First, it was a biostat that reacted partly with gelatin and remained in the coating for a long long time, killing microorganisms. The second, and main purpose was that it reacted with leftover coupler and linked it together with itself in a bond called a methylene bridge. This prevented serious dye fade. That latter problem has been solved in modern C41 films, but has not in E6 films due to lack of R&D.

PE

Yes, that long post should be here.

Yes, here it is! (there was a url link here which no longer exists)

PE

Many thanks PE, both for your reply to this thread and your excellent information about this stabilizing business!

/Bertil