I'm getting yellow stains on my fiber prints, and can't figure out what is causing them. There might be just one little spot, or a couple, or a thin (1/16 in wide and two inch long) streak. the color is like ferrocyanide solution. Have tried changing to new gloves to handle the prints, but that hasn't resolved it.

Any thoughts would be appreciated.

-- Allen Birnbach (birnbach@earthlink.net), June 27, 2001

Answers

It's hard to tell what's causing it with the info you've given>Basically,anything could have happened!..But i can give you a general advice which might help.After you transferred the print from developer to stop, make sure -absolutely sure- that you neutralized all traces of developer on your hands (or rather gloves)in the stop bath.One advantage of using bare hands over gloves is that you know exactly where you have developer on your fingers.It's not easy to feel this with the gloves on.If there are traces of developer left on your fingers and they come in contact with the print after you pick it up from the fixer, this can cause staining.If your fixer is "not so fresh", this would make matters even worse.Of course, some will say if yuu use tongues, this wouldn't happen, but i recommend learning to handle prints more carefully instead. I also found out, by experience, that some papers stain easier than others and some are more resistant.Forte papers, especially warmtone, is the worst in this regard.You must handle this paper with extreme care.

-- Cem Topdemir (cem-1@softhome.net), June 27, 2001.

The most likely cause is an Iron stain from the sound of it.
This could be coming from a rusty water pipe or fitting, from some general contamination of your water supply, or from a cracked enamel dish.
I think there's a simple test for Iron, but I can't for the life of me think what it is at the moment (potassium dichromate?).

-- Pete Andrews (p.l.andrews@bham.ac.uk), June 28, 2001.

>If there are traces of developer left on your fingers and they come in >contact with the print after you pick it up from the fixer, this can >cause staining.

Cem-To clarify. You mean that if there is developer on my gloves and the print goes through the stop bath and then into the fix, the latent developer on the glove will stain the paper then? I figured once an image was fixed, it was impervious. Still learning after all these years.

By the way, I did all my printing bare handed for years, and recently switched because of concerns for absorbing the chemistry through the skin. Just seems prudent.

-- Allen Birnbach (birnbach@earthlink.net), June 28, 2001.

Alan,yes, that's what i meant.It won't form an image but can cause staining.It won't appear right away, you may see it after the print dries.I must tell you that this is not something i read in darkroom or chemistry books but discovered the hard and painful way,-i learnt most what i know by actually doing it, and talking to other printers- so there's a chance i'm attributing it to the wrong cause, but i once asked about this to George Tice and we seemed to agree, plus my reasoning is better safe than sorry.So, if in doubt, when the print is in the fixer, i sometimes put my fingers back in the stop bath, just to make sure, stop bath is pretty harmless as far as contamination.I guess it can also depend on the particular type of developer, there are just too many variables.There are more knowledgeable people about the specifics of chemistry on this board than myself, matbe they can tell you if and why.Of course, your stains may be caused by something else alltogether.Does it happen occasionally or pretty much on every print? If it is consistent, it could be something in the water, as Pete said.

On a side note, i find Ilford papers most resistant to contamination in general.This shouldn't be a factor in one's choice of paper though.

I sometimes use gloves when toning, but not when developing.I certainly agree to being prudent, everyone has his/her own ways of working.I think the best protection is to develop "good" darkroom work habits, careful handling of paper and chemicals and to use plain common sense,If i am sloppy, neither tongues nor gloves will protect me.

-- Cem Topdemir (cem-1@softhome.net), June 28, 2001.

So, if in doubt, when the print is in the fixer, i sometimes put my fingers back in the stop bath, just to make sure, stop bath is pretty harmless as far as contamination.

If you dip your gloved fingers in the stop bath then into the developer later, won't this decrease developer activity? In other words, won't an acidic stop bath contaminate the developer?

Allen, if you change gloves before (?) handling the print then I don't see how you're getting developer or even stop bath residue on them. How do you wash your fiber prints? How long do you wash them?

-- Bong Munoz (bong@techie.com), June 29, 2001.

First, my apologies to Allen for misspelling his name.

Bong, why would you put your stop bathed gloves back in the developer.I guess we do things a bit differently, the order of my tray is developer -> stop -> fixer.And i don't start on a second print until after the one i'm working on is finished, as i constantly agitate each tray.

-- Cem Topdemir (cem-1@softhome.net), June 29, 2001.