Questions about B&W film reversal

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I believe you're talking about Copper bleach here. Looks like the first step (negative silver image to silver chloride) worked but the second one (clearing of silver chloride) didn't. Check your Ammonia. It needs to be at least 2% and reasonably fresh.
 

MCB18

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Ferric chloride, actually. Not copper. And I used a bit of ammonia straight from the bottle, should be 10%, but might be a bit less now. Smelled fucking awful so I know it’s still good..
 
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dcy

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Whoo hoo! Success!

I did the same bleach test as @MCB18 --- Fully exposed the film, develop, stop, bleach steps, and clearing bath. --- I have the ingredient to make all three bleaches, so I decided to use ferric chloride to match @MCB18. Because I was curious about the role of sodium sulfite, I did two tests:

Test 1: Bleach ---> Ammonia ---> Sulfite sequence (i.e. reverse sequence).

Test 2: Bleach ---> Sulfite ---> Ammonia sequence (i.e. "default" sequence).

Note that the video describing the variant with ferric chloride uses the reverse sequence, but it also uses sodium metabisulfite, and that might be an important difference. Without further ado, here are the results:



As you can see, the reverse sequence left a significant amount of stain, which was avoided with the "default" sequence. The intended purpose of the sulfite bath is to prevent staining. It appears that it is indeed an important step for the ferric chloride bleach.

I also noticed that the solid precipitates looked very different. When ammonia came first, the film formed some fairly large "flakes" of red material. I don't know what that is. Silver chloride should not be red. But when the sodium sulfite bath came first, the red material was a fine powder that drifted off into the liquid easily.

Here are close-ups of the results with the reverse sequence:





And here are close-ups of the results with the default sequence --- don't mind the mark on the film; I was just too aggressive with the tongs and scratched the film.


 
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dcy

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Ferric chloride, actually. Not copper. And I used a bit of ammonia straight from the bottle, should be 10%, but might be a bit less now. Smelled fucking awful so I know it’s still good..

Let's see if we can diagnose this. Today I tried the same test as you and I got good results. Let's see... this is what I did:

Exposure: I exposed the film to room lights and held the film close to a lightbulb.

1st Developer: Paper developer with a strong dilution (Eco Pro 1+4) for 10 full minutes.

I am 100% sure that this is way overkill, but I really wanted to make sure that 100% of the silver was developed. The easiest way for the test to fail is if the initial development is insufficient.\\

Stop Bath: 2 minutes.

Bleach: Ferric chloride with water in a 1+1 ratio for 5 minutes.

Sodium Sulfite Bath: 2 minutes. ---- Causes a red powdery substance. The liquid gets quite "dirty".

Ammonia Bath: 2 minutes. ---- This might have been the stage when the film turned transparent, but I'm not sure. I couldn't get a good look at the film when it was inside the sulfite bath.

Wash: 2 minutes under the faucet. I actually scrubbed the film with my (gloved) fingers.

2nd Developer: I just put the film back in the same developer for another 3 minutes.

Did not see any development at all. The film stayed just as clear as when it came out of the ammonia bath.

Stop Bath: 2 minutes.

Fixer: 2 minutes.



Do any of these steps look different from what you did?
 
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dcy

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Try a more regular, dependable bleach.

AFAIK the only beaches that fit that definition are the "classic" potassium dichromate or permanganate bleaches. The purpose of all the XXX-chloride bleaches is to pick something a little less harmful.

After the potassium dichromate and permanganate bleaches, the next most "regular" bleach uses sulfuric acid.

Beyond that, I think every bleach has had its share of reported failures. @relistan has had limited success with his efforts to make citric acid work.
 

MCB18

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I have been doing the clearing bath after the ammonia. I also use Dektol 1+3 for about 3-4 minutes.

Are you guys doing all of this in room light by chance? I have been because I didn’t think it mattered for this test?
 

koraks

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After the potassium dichromate and permanganate bleaches, the next most "regular" bleach uses sulfuric acid.
If you apply some sensible work practices, you end up with some chromium (III) or metallic manganese, neither of which are major concerns either way, and some sulfate. Not so pretty if you use kilos of the stuff, but the few grams you need to process a box of film...well. Let's not exaggerate. If you want to steer clear of the dichromate, which I can very well imagine, permanganate is in my view a perfectly reasonable alternative. It's sold to combat fungal infections in Koi fish and to disinfect water in survival situations, to name a few. Again, not nice if you dump a kilo into a nearby stream. In small amounts, just not much of a concern. I honestly don't see the problem with sulfuric acid if people use hydroxide to make their developer concentrate without batting an eye, or glacial acetic acid to mix a stop bath. Risk perception and management in home darkroom situations can be a really funny, irrational affair much of the time.
 

Donald Qualls

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After the 2 bleach steps and clearing bath, the film was still opaque and yellow, and when put in developer again it turns almost completely black.

This indicates the rehalogenation is working, but dissolving the silver chloride isn't. Either your ammonia bath isn't doing the job (warmer, longer time in bath, or stronger ammonia would be the things to try) or the silver is being converted to a different halide -- bromide or iodide instead of chloride.
 
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MCB18

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This indicates the rehalogenation is working, but dissolving the silver chloride isn't. You're using copper sulfate bleach?
Ferric Chloride.

I took a picture of it today after another test:


And after second development:
 

Donald Qualls

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Right. The ammonia isn't dissolving the rehalogenated (and exposed) silver. See my edit above -- warmer, longer bath time, or stronger ammonia are the things to try. Make sure you have only pure sodium chloride as the halide donor in the bleach bath, no bromide or iodide (I don't know how much trouble the tiny amount of iodide in table salt would cause, but use kosher or non-iodized if that's your source of additional chloride. You might also check that fixer will dissolve the yellow halide, just to be sure it isn't some other silver compound that's developable, but not soluble in ammonium hydroxide.
 

MCB18

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So, my bleach is literally just ferric chloride 1:1 with water. Give me a minute and I can show you the bottle of ferric chloride. There shouldn’t be any bromine or iodine in there at all.
 

Donald Qualls

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There shouldn’t be any bromine or iodine in there at all.

Is this circuit board etching solution, or lab grade ferric chloride? Etching solution might have stuff in it to make it work better on copper...
 

MCB18

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Is this circuit board etching solution, or lab grade ferric chloride? Etching solution might have stuff in it to make it work better on copper...

It’s this stuff.
 

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dcy

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dcy

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I have been doing the clearing bath after the ammonia. I also use Dektol 1+3 for about 3-4 minutes.

Looking at the pictures you posted, that's definitely a lot more than just a stain. Based on my experience, it's best to do the clearning bath first, but I am sure that that's not what's going wrong with your setup.

It really looks like the developer developed the film again. Like @Donald Qualls said, the ammonia is not dissolving the AgCl for some reason.

Are you guys doing all of this in room light by chance? I have been because I didn’t think it mattered for this test?

Yes. 100% lit room. Even intentionally held the film close to the light bulb for 30 seconds. I did everything inside beakers and mason jars, all 100% transparent.

So, my bleach is literally just ferric chloride 1:1 with water. Give me a minute and I can show you the bottle of ferric chloride. There shouldn’t be any bromine or iodine in there at all.

I am using the same dilution, and just regular tap water. We also established that I have exactly the same ferric chloride product that you have.

Hhhhmmm...

Let's see... We ruled out the ferric chloride, we ruled out the ferric chloride dilution, the developer looks good... Could the problem be in the ammonia bath?

Q: What did the film look like after the ammonia bath? It should be clear. Like... absolutely clear. Just the film base. When I held my film to the light it was obvious that the 2nd developer wasn't going to do anything and I just put it int he developer to confirm.

Q: What are you using for the ammonia bath? I used the regular ammonia cleaner from Walmart. The house brand. No dilution at all.
 
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YoIaMoNwater

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Are you guys using tap or distilled or deionized water for the bleach and clear baths? Tap water has chloride ions that affects the bleaching ability: https://unblinkingeye.com/Articles/PBR/pbr.html



Also just re-reading it again, ferric chloride... so you probably have free chloride ions that's causing all these issues. Where did you guys read that this is a useful bleach for black and white reversal?
 
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dcy

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Are you guys using tap or distilled or deionized water for the bleach and clear baths? Tap water has chloride ions that affects the bleaching ability: https://unblinkingeye.com/Articles/PBR/pbr.html

Good thinking. I used distilled water for both.

@MCB18 Are you using tap water?

Also just re-reading it again, ferric chloride... so you probably have free chloride ions that's causing all these issues. Where did you guys read that this is a useful bleach for black and white reversal?

The first post of this thread links to the sources for every recipe. In the case of ferric chloride for B&W film reversal, that came from this video. The video demonstrates successes, and as I posted earlier, I had no trouble getting a clear film from the bleach.
 

MCB18

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Also just re-reading it again, ferric chloride... so you probably have free chloride ions that's causing all these issues. Where did you guys read that this is a useful bleach for black and white reversal?
This is the point. It’s a regal bleach meant to turn Ag into AGgCl. Putting clouded ions in solution is the entire point.

This is after both bleach steps and the clearing bath.

Q: What are you using for the ammonia bath? I used the regular ammonia cleaner from Walmart. The house brand. No dilution at all.
I just used the 1 gallon container of ammonia you can get from Ace Hardware.
 

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dcy

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I mean, the photo I shared previously was after the bleach and clear baths.

Oh. Alright.

Well, the first photo (after the bleach + baths) clearly isn't transparent. I don't understand what's going on, but it looks like the baths didn't even touch the film. When I did this, the effect of the clearing baths was unmistakable. You could immediately see the film spitting out red dust and becoming clear.

I'm going to think more about this, but right now I am out of ideas. How could the baths have done absolutely nothing?

What film are you using? --- I can't imagine anything in the film that could make the baths do nothing at all, but I don't know what else to ask.

Oh, there's also the question about whether you're using tap water or distilled water. ---- Earlier I said I used tap water, and then I changed my mind and said it was distilled water. Now I'm doubting myself. I honestly cannot remember.
 
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Completely agree. And if one wants to avoid handlng Sulphuric Acid directly when making the bleach, Sodium Bisulphate crystals can be used as a substitute.
 
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dcy

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And if one wants to avoid handlng Sulphuric Acid directly when making the bleach, Sodium Bisulphate crystals can be used as a substitute.

There is nothing wrong with experimenting with chemistries for film reversal. No-one is breaking any rules if they want to experiment with using citric acid, or ammonium chloride, both of which were done by @relistan in the copper sulfate thread, or sulfamic acid, or ferric chloride, both of which I suggested in the first post of this thread. I obtained chemistry to do several of these types of bleach and I will enjoy experimenting with them at my leisure. I grabbed the ferric chloride only because that's what MCB18 chose and I wanted to see if I had the same problems.
 
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Relax. Where did I say anything about you experimenting that warranted the above response?
 
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