Tetenal E6, milky BX part 2?

Rudeofus · Dec 19, 2011

I have used the Tetenal 5 liter E6 3-bath kit for some time now and remember the BX part 2 concentrate as fully transparent liquid. I usually mix about 500-700ml for each multi run and seal the containers with the concentrate after applying a healthy dose of Protectan. The concentrate is stored in the basement where it is cool but not below freezing point. I have successfully used one such kit in the course of over a year without any visible changes in the concentrates.

For some mysterious reason the BX2 part (the part which looks more like fixer than like bleach) of the concentrate I have been working with for the last half year has turned into a white, milky liquid. The chemistry still seems to work - the slides look as expected, but I would really like to know what happened here. Unlike FD, CD and bleach the effect from incomplete fixing isn't necessarily obvious right away but may bite me later. Of all the components of the E6 kit the one which looks like fixer was certainly the last one I would have suspected of going bad - in the middle of winter.

Has "milky" BX2 gone bad or is this completely harmless? Is there some way I can replace the BX2 with home brew chemicals? If indeed only fixing is incomplete, is there a chance I can redo this step with b&w fixer?

pukalo · Dec 19, 2011

Personally, I'd save the rest of this kit for unimportant rolls, test rolls, playing around type shots. Or just discard it. You dont need to find out 5 years from now the chems went bad and your slides are color shifted and or trashed. If you got close to a years use out of the kit, you got your moneys worth, and then some. Time to order a fresh kit from Maco Direct. Runs around $125-150US, shipping included for the 5 Liter kit which will run up to 60 rolls. Or, order the Tetenal E6/C41 Stabilizer from Maco and get the Arista kit from Freestyle Photo here in US. Just went thru the Arista 1 Gallon kit, with good results. Have a Tetenal kit waiting to be opened, to compare.

Rudeofus · Dec 20, 2011

Thanks for your reply! Sure, the easiest way would be to just toss out the old dev kit and start with a fresh kit. The kit which causes the problems is only half a year old, I used the previous kit over a whole year without problems. I did store the previous kit in my fridge, not in the basement, so that may be the difference, I just don't like the idea of smelly poisonous chemicals in my fridge. The thing that surprised me most was that it seems to be the fixer which changes, I would have expected the FD or CD to be the first ones to go bad. Since colors and brightness are ok, I assume that FD, CD and BX1 are still in good working condition.

I will try refixing the leader of that film roll in b&w fixer, I am curious whether it makes a (positive and visible) difference or not. To my untrained eye this recipe doesn't look all that different from b&w fixer. I will report on my progress.

Rudeofus · Dec 21, 2011

For all who care: Tetenal tech support confirmed that my BX2 is dead and that I shouldn't use it.

Photo Engineer · Dec 21, 2011

The milky fluid is bad! Don't use it.

For a replacement, get some C41 fixer or something similar.

PE

pukalo · Dec 21, 2011

refrigeration is also bad - check your Tetenal Box, it has a Minimum storage temperature specified.

Rudeofus · Dec 22, 2011

pukalo said:
refrigeration is also bad - check your Tetenal Box, it has a Minimum storage temperature specified.

Funny thing is the kit I stored in the fridge lasted for a whole year opened, while the kit I stored in my basement lasted less than half a year. The problem may be completely unrelated to my storage, Tetenal asked for the number printed on the container.

So I am still stuck with the question: can I use B&W fixer to refix the color slides or do I have to play games with the pH value or other compounds?

Photo Engineer · Dec 22, 2011

You can use a neutral B&W fixer without hardener for a substitute E6 fix. Do not use any acid or alkaline fix, nor any with hardener.

PE

Rudeofus · Dec 22, 2011

Thanks, PE, for your advice. Now let's assume I have some standard B&W fixer (e.g. Ilford Rapid Fixer), which is, AFAIK acidic. Is there an easy way to make it neutral without destroying its properties or is it better to home brew mix something from scratch?

Photo Engineer · Dec 22, 2011

It is ever a good idea to modify a formula without knowing what is in it. You run too great a risk with your image stability when it comes to color. If you adjust it must be between 6.0 and 6.5. I would use 28% Acetic Acid and 3% Ammonium Hydroxide as a guess and be very careful. The adjustment may cause other problems.

PE

Rudeofus · Dec 23, 2011

So rather homebrew? In the link I posted above the following recipe was specified:

Derek Watkins' E6 fixer said:
Sodium thiosulphate (Na2S2O3 * 5 H20) 200.0 g
(or anhydrous 125.0 g)
Sodium sulphite, anhydrous 5.0 g
Sodium metabisulphite (Na2S2O5) 0.5 g
Water to 1 liter

I just confirmed that I can obtain all these chemicals without any special license or permit from our local pharmacy. Are there any potential pitfalls with this recipe? Is there anything I can do if the pH value comes out way wrong (why would it anyway)?

Rudeofus · Jan 3, 2012

I mixed a new batch of fixer according to the recipe posted previously and tested the film leader of one roll. The leader was previously souped in the broken soup and consists both of a fully exposed and a completely unexposed part. I dipped only part of the exposed and part of the unexposed half in the new fixer so I was able to observe the effect of the new fixer.

Here are the results:

Immediately after submerging the fully exposed part the film became translucent. Unlike B&W film which eventually clears up in fixer the slide film stayed translucent, even after about 10 minutes in the fixer with agitation.
After washing, stabilizing and drying the translucent part became fully transparent again.
There is NO observable difference between the parts I submerged in the fixer and those that received no treatment.
The BLIX which started off milky has in the mean time precipitated lots of sulfur, which suggests is has turned completely unusable by now.

Since there is no visible difference between film parts receiving extra fix and those without I assume that the films processed two weeks ago were properly fixed. Correct me if I am wrong here, please. Since the BX2 part seems to have gone completely bad by now I should no longer mix any BLIX with it. Either I can replace the BX2 part with some home brew recipe or I have to mix bleach and fixer myself (maybe use the recipe posted here).

I will push Tetenal hard to send me a BX2 bottle, this is a component which shouldn't go bad under normal circumstances.

Photo Engineer · Jan 3, 2012

Well, something went wrong with the BX2 as it went bad. If it is on the edge, and you mix a blix from it, then you push it over the edge and speed up decomposition. Blixes made up for film are less stable and that is one of the reasons I advise against using them.

You can substitute any neutral, non hardening fixer for the part 2 or you can make a bleach then fix with those same ingredients. I use C41 fix in a pinch as it works very well for all films, color or B&W.

PE

Rudeofus · Jan 4, 2012

Thanks again, PE, the reason I use BLIX is not because I love it so much but because that's what comes with the kit you get here in central Europe. People who have condemned BLIX here with all furor have so far conceded that the Tetenal BLIX is at least ok. It has worked well for me for several years, but now it has failed for me. By the way, it wasn't the BLIX but one of its mixing parts which failed, the problem is already visible in the concentrate.

Someone here in the forum had (there was a url link here which no longer exists) when he mixed a bleach from BX1 and a separate fixer from BX2, so this seems to be a poor option when using Tetenal chemistry. So I am basically left with three options if I want to continue using most of the remaining chems:

Toss the still working Tetenal BX1 and mix a separate bleach and fixer with the Watkins factor recipe
Toss the still working Tetenal BX1 and use (there was a url link here which no longer exists) from (there was a url link here which no longer exists). Not sure whether PE's C41 bleach works for E6 as he has (there was a url link here which no longer exists) that the bleach demands for C41 and E6 are a bit different.
Mix the Tetenal BX1 with water and adjust its pH to make it more active so I don't get the poor results naugastyle got, then use the fixer from Watkins factor. Funny thing is that the Watkins factor recipe for fixer is much more dilute than the recipe posted (there was a url link here which no longer exists). Any ideas which one is more suitable?

Any insights on this?

Photo Engineer · Jan 4, 2012

4th option: Use any neutral fix or C-41 fix in place of BX2 and mix BX1 and this fix as called for in the Tetenal recipe. That makes a pretty good blux but it may take 2x the time. The way to check it out is to keep an eye on the highlights and go for 2x the time to clear them just like B&W. Then add 1 min or so for safety!

PE

Rudeofus · Jan 4, 2012

Photo Engineer said:
4th option: Use any neutral fix or C-41 fix in place of BX2 and mix BX1 and this fix as called for in the Tetenal recipe.

Just to make absolutely sure I understood what you try to tell me here: I take 200ml of BX1 concentrate, almost 800ml of water and add Na2S2O3, Na2SO3 and Na2S2O5 according to one of the recipes, then top off to 1 liter and I should have a working BLIX? Or should I leave out Na2SO3 and Na2S2O5 and only use Na2S2O3? Since the FD part only lasts for 2 weeks once mixed I don't care that much about long term stability of the BLIX.

Edit: Oops, I remember there shouldn't be excessive Na+ is the bleach/BLIX. Would (NH4)2S2O3 alone do the job?

Photo Engineer · Jan 4, 2012

That is not what I said. A blix for any color film should contain NO Sodium salts. All you have listed should be Ammonium salts instead. The C41 fix is all Ammonium!

So, take 1 bottle of BX1 (the red part) and the equivalent to one bottle of BX2 but use C41 fix here. Mix the two and dilute to the volume for this amount of concentrate.

If you wish to mix from scratch use the three salts above as their Ammonium counterparts. That set of formulas you are referring to is totally incorrect in several ways. One of them is the use of Sodium salts.

PE

Rudeofus · Jan 5, 2012

Photo Engineer said:
That is not what I said. A blix for any color film should contain NO Sodium salts. All you have listed should be Ammonium salts instead. The C41 fix is all Ammonium!

I corrected this shortly after posting the original message. Would (there was a url link here which no longer exists) do the trick? Or is this still too heavy on the Na+ side? If I substitute the Na2SO3 with (NH4)2SO3, the pH will be too low, is there something I can add to get the pH to neutral again without introducing other adverse effects?

Photo Engineer said:
If you wish to mix from scratch use the three salts above as their Ammonium counterparts. That set of formulas you are referring to is totally incorrect in several ways. One of them is the use of Sodium salts.

Could it be that the BX2 component contains the required Br- and this is why (there was a url link here which no longer exists) had such poor success with separate BX1 and BX2 bathes? Am I correct that brown negs indicate incomplete bleaching? Would it be a good idea to add a gram of NaBr or NH4Br to my BX2 substitute just to be sure? Unfortunately the nice test for Br- based on AgNO3 won't work when there is so much thiosulfate around or I would have checked the BX2 soup

It's naugastyles posting which worries me most about messing with the BX1 component and home brew fixer. To add insult to injury, I have not found a source for (NH4)2 FeIII EDTA or (NH4)2 EDTA so any experiments with home brew bleach will be based on either using BX1 or going the Ferric Cyanide path (I know, I need a stop/clearing bath for this to work).

Thanks for your generous help so far, PE!

Photo Engineer · Jan 5, 2012

Any fix for color must contain a sequestering agent to give the solution a small excess to prevent Iron stain. Since IDK what BX1 is comprised of, I cannot say if Ryuji's fix would work as is. You may have to add about 5 g/l of EDTA and rebalance the pH. TF5 and the C41 fix have both been formulated for this eventuality.

As for making up a blix or bleach for film, you can use EDTA + FeCl3 (Ferric Chloride) 1 mole to 1 mole and then add 10% Excess EDTA. Adjust the pH to 6.5 with Ammonium Hydroxide and Acetic Acid as needed starting with the ammonia. You can use FeBr3 instead. This gives you the halide salt.

Brown stains can be incomplete bleaching, incomplete fixing, a combination of both or retained iron stain due to low excess EDTA.

Glad to try and help.

PE

Rudeofus · Jan 5, 2012

Ron, I finally found your recipe for C41 fixer (there was a url link here which no longer exists)! You have posted so many recipes and valuable hints that this little gem got flooded under all the other info bits you have supplied over the last couple of years.

So here's my new (and hopefully final) approach for E6 BLIX based on BX1 and homebrew:

mix 120g (NH4)2S2O3 with water to make 200ml
quickly add 10g of Na2SO3 and 2g of Na2EDTA
add 50g of NH4Br. I don't know yet whether that's necessary but right now I am not sure whether there is any Br- in the BX1 part. naugastyles results suggest it is not and must therefore be added to my soup. If he could observe brown negatives through the orange mask this was not just a little iron or silver halide stain, but that's just conjecture. I have collected 8 FeIII-EDTA based recipes for C41/E6 bleach and the Br-/I- varies between 1g/l and 150g/l so I'm not 100% sure about the optimal quantity ...
add 500 ml water, use acetic acid to adjust pH to about 6.5. I know, your recipe states I should adjust the whole liter to a pH of 6.5 but frankly a pH so close to 7 shouldn't change much with a bit more or less water. pH is a logarithmic measure after all.
measure 200 ml BX1 and add to the soup.
add water to make 1l of solution

Photo Engineer · Jan 5, 2012

Without knowing the concentration or ingredients of BX1, I would say that this looks good.

Best wishes.

PE

Rudeofus · Jan 5, 2012

Since I also don't know the ingredients of BX1 and Tetenal is not exactly forthcoming with information either I will order the chemicals and mix that soup in the next few weeks and report the results here in this thread. Thanks for your support, Ron!

Tetenal E6, milky BX part 2?

Privacy & Transparency

Privacy & Transparency