Removing dust or fixer sediment from negatives

[Joey Pasco]

Hi all,

Lately I've been having what I originally thought was a dust issue, but after some poking around on APUG, I'm now convinced it's sediment build-up in the fixer that has made it onto my negatives.

My question is, what is the best way to clean these specks from my film?

Should I pre-soak, re-fix (with new fixer), and re-rinse (+PhotoFlo) & dry?
Or would just a rinse +PhotoFlo do the trick?

I'm hoping these negatives aren't a lost cause.

Thanks in advance!
Joey

 

[tedr1]

Probably further fixing is unnecessary.

Possibly use rinse with a very soft brush to persuade the particles to leave without scratching the film?

I never heard of sediment in fixer.

 

[RauschenOderKorn]

How does the negative look like? Can you see the spots on the negative or only after scanning?
If you can see them, on which side of the negative are the spots?
As you indicate this is "sediment built up in the fixer" - how do you fix your film, why do you think so?

 

[Agulliver]

If there is some substance on the film, it is safe to clean developed and fixed film with isopropyl alcohol and a gentle cotton wipe.

 

[Scott Micciche]

I have been filtering my fixer through a coffee filter to avoid particle spots like this. Solution B of PMK Pyro has a ton of particulate that I also filter.

 

[Sirius Glass]

Every post has good ideas:

• filter chemicals
• wash and PhotoFlo or equivalent
• isopropyl alcohol and a gentle cotton wipe

Welcome to APUG​

 

[Pat Erson]

To me it looks like a Photoflo issue, an improper use of this wetting agent.

 

[Doremus Scudder]

I have been filtering my fixer through a coffee filter to avoid particle spots like this. Solution B of PMK Pyro has a ton of particulate that I also filter.

Off-topic but important: If your PMK Sol. B has "a ton of particulate" it's because you aren't using distilled water for it. PMK B is a saturated solution of sodium metaborate. Any impurities at all in your water and a good portion of the metaborate will not go into solution. Be aware that you are likely dealing with a reduced activity when using that batch of Sol. B, so don't base any test results on it.

You might try to filter out the precipitate and dissolve it in distilled water. If you can get it to go into solution, you can add it back to the Solution B and just calculate the extra needed for developing based on the extra volume (twice the volume is an easy calculation). However, if the precipitate is now insoluble, then you'll have to deal with the weaker Solution B. If it's within your working prameters, just use it. If you seem to be getting weak results, you may want to discard it, get some sodium metaborate and mix a new Sol. B in distilled water.

Best,

Doremus

 

[Joey Pasco]

Update: I disposed of my old fixer to mix a new batch, and the bottle had SO much sediment in it (a lot of it stuck to the inside walls and the bottom of the bottle) that I decided to get rid of the bottle itself and use a new one. Results: Zero issues on the rolls I've processed since mixing the new batch.

For the curious, I use Ilford Rapid Fixer.

I think the main cause of the problem was silver sediment sticking to the inside of the bottle, which I didn't notice when mixing new batches of fixer. So even though it was a new batch, the sediment was still present, and only increased as I used and reused the fixer (gathering more silver particulate along the way).

 

[Scott Micciche]

Off-topic but important: If your PMK Sol. B has "a ton of particulate" it's because you aren't using distilled water for it. PMK B is a saturated solution of sodium metaborate. Any impurities at all in your water and a good portion of the metaborate will not go into solution. Be aware that you are likely dealing with a reduced activity when using that batch of Sol. B, so don't base any test results on it.

You might try to filter out the precipitate and dissolve it in distilled water. If you can get it to go into solution, you can add it back to the Solution B and just calculate the extra needed for developing based on the extra volume (twice the volume is an easy calculation). However, if the precipitate is now insoluble, then you'll have to deal with the weaker Solution B. If it's within your working prameters, just use it. If you seem to be getting weak results, you may want to discard it, get some sodium metaborate and mix a new Sol. B in distilled water.

Best,

Doremus

The solution b is actually pre-mixed from Photographer's Formulary, which has some crystals.. I always use distilled water, in all my steps.

 

[Doremus Scudder]

The solution b is actually pre-mixed from Photographer's Formulary, which has some crystals.. I always use distilled water, in all my steps.

If you have the PF pre-mixed PMK, they definitely used distilled water for Sol. B, so no need to worry. You likely don't have a large amount of precipitate. FWIW, PF and others recommend you shake Sol. B before using. Small particulates from solution B will dissolve once diluted to working strength.

I've been using PMK for years and mix it with tap water (stock solution are made with distilled). All steps except for the final rinse with wash aid are done with tap water.

Best,

Doremus

 

[John Wiegerink]

I learned my lesson the hard way! I always filter my fixer and my replenished Xtol. The only thing I don't filter is quick-mix one-shot developers. Oh, and I always use distilled water. Fixer has always been a problem for me and that's why I now filter it.

 

[Scott Micciche]

If you have the PF pre-mixed PMK, they definitely used distilled water for Sol. B, so no need to worry. You likely don't have a large amount of precipitate. FWIW, PF and others recommend you shake Sol. B before using. Small particulates from solution B will dissolve once diluted to working strength.

I've been using PMK for years and mix it with tap water (stock solution are made with distilled). All steps except for the final rinse with wash aid are done with tap water.

Best,

Doremus

Thank you very much for the tips! I should do a more vigorous shake and with warmer weather approaching, maybe more will dissolve. Yes, I do not have large chunks, just small enough to make spots in the emulsion.

 

[Doremus Scudder]

Thank you very much for the tips! I should do a more vigorous shake and with warmer weather approaching, maybe more will dissolve. Yes, I do not have large chunks, just small enough to make spots in the emulsion.

If the particulates do not go into solution in the diluted developer, you'll need to filter them out. Ideally, Solution B is just sodium metaborate and distilled water. If the water quality is not great or if the metaborate is not pure, you can get insoluble particulates floating around. These are unwanted and can stick to the emulsion. Certainly, you should not be developing negatives in developer that contains particulates. I have been using PMK for years now and have never had a problem with particulates in the working solution, even though there are some in the Solution B bottle. If you've had problems with particulates from the developer adhering to negatives, I'd filter everything. Keep in mind that the usual culprit for depositing particulates on negatives is re-used and/or too old fixer, not the developer.

Best,

Doremus

 

[Gerald C Koch]

Particulates that get embedded in the emulsion are very hard to remove. In addition if one IS successful the particulate usually leaves a mark in the emulsion. Best to prevent them in the first place.

 

[georgegrosu]

Joey, your problem may have two causes:
- impurity glued on the film emulsion (silver grain with gelatin);
- an impurity inside of the emulsion layer.
If impurity is on the emulsion surface is chances to remove.
Use an alkaline solution of sodium carbonate (20 g / l) for 2-3 minutes at 20-25 ° C.
Gelatin emulsion layers will swell, and the impurity is more likely to be eliminated.
Wash with water about 5 to 10 minutes after which a solution PhotoFlo used to prevent water stains.
If the impurity is inside the emulsion you have no chances to remove.
It is a problem that comes from the film.
To set where is the impurity (on the emulsion or in the emulsion) using a magnifying glass with reflected light.

I use isopropyl alcohol for wiping grease stains, oil on the film.

George

 

[Joey Pasco]

Thank you all for your input and advice!

Joey, your problem may have two causes:
- impurity glued on the film emulsion (silver grain with gelatin);
- an impurity inside of the emulsion layer.
If impurity is on the emulsion surface is chances to remove.
Use an alkaline solution of sodium carbonate (20 g / l) for 2-3 minutes at 20-25 ° C.
Gelatin emulsion layers will swell, and the impurity is more likely to be eliminated.
Wash with water about 5 to 10 minutes after which a solution PhotoFlo used to prevent water stains.
If the impurity is inside the emulsion you have no chances to remove.
It is a problem that comes from the film.
To set where is the impurity (on the emulsion or in the emulsion) using a magnifying glass with reflected light.

I use isopropyl alcohol for wiping grease stains, oil on the film.

George

Thanks George, that's very thorough!

 

[Gerald C Koch]

I never heard of sediment in fixer.

Happens all the time especially when the fixing bath begins to sulfurize. It's a good idea to filter solutions that are reused before each use.

If the particles that the OP is seeing are sulfur then he is SOL unless they can be mechanically dislodged since sulfur is not soluble in anything that would not also damage the film.

 

[tedr1]

I tend to use solutions in a single session.