FB Prints Yellowing within a Few Minutes of Processing

I don't have a huge amount of experience with FB paper(I normally use RC) but am throwing together a bunch of prints to give as gifts and thought the extra trouble of FB would be worth it for this.

 

For background information, not that it particularly matters, these are printed from a 6x6 Tri-X negative, and the paper is Ilford "glossy" FB MG(green/pink label). I doubt it matters, but it's also printed through an Ilford 1 1/2 filter. The paper SHOULD be fresh-I just opened the box last week, and think I bought it from the local camera store about 6 months ago. I don't see an expiration date on it, and it could be a few years old given that I don't think FB paper is a super high volume product for them, but anyway it also shouldn't be terribly old.

 

I had yellowing issues last week, so spent some time before I started for this evening scrubbing all of my trays out spotless. I bought the trays used, but the previous owner did put a "D" on the tray I use for developer and "F" on the one I use for fixer.

 

I developed in Dektol that I mixed last month and diluted 1:3 just before starting this evening. I'm using Ilford Rapid Fixer, also diluted this evening at 1:4. The Hypoclear I'm using was something I prepared myself, but should be equivalent to Kodak Hypo Clear and was also diluted 1:4 right before use this evening.

 

I'm otherwise following the procedure on this page

 

ILFORD optimum permanence wash sequence for FB papers

 

I was using an old GraLab analog timer to time everything, and kept resetting it for 5 minutes. So, in accordance with the above, I did the following:

 

1. After developing, I gave the paper a quick rinse under running water then fixed for 1 minute, possibly +5-10 seconds.

 

2. I went into the sink with running water for 5 minutes(again by the timer), generally going a few seconds longer

 

3. I went out of the sink into the tray of hypo clear, where it stayed for two 5 minute cycles on the timer

 

4. It then went into the sink again for another 5 minutes under running water

 

I did these "assembly line" style, so had at least one print in 1st wash/hypo clear/second wash at any one time(although I tried to avoid overlapping my washing too much). The first print didn't get lined up properly in the easel, so it's trash but I wanted to go through the full process/wash on it anyway to test it.

 

In any case, out of 4 prints this evening, the 1st and 3rd yellowed-I don't show the first, but it was quite dramatic. The 3rd isn't as dramatic, but is there. The 2nd and 4th are fine. I'll also add that all were fine when I first turned the room lights on(which was after all had spent at least a couple of minutes in hypo clear) but started yellowing after that-the middle print of the below started yellowing while still in the hypo clear.

 

Does anyone have any ideas about where I may have gone wrong here? I guess I've gotten use to being sloppy with RC prints, and have never had issues with them yellowing(including the test prints I did on RC last week to nail down exposure/contrast).

 

Fiber based paper requires a longer fix time even in fresh fix, I give mine at least 5 minutes, some papers I give 10 minutes. Check the info sheet that came with the paper, it should give you the correct range of fix times.

Not enough fixing can cause bad effects, but it normally is on the scale of years, or maybe only months.

 

I suppose not rinsed at all, it could be days.

 

I have had RC prints that were sometimes in direct sunlight turn brown after some years.

 

The rule before hypo clearing agent was that you timed from when you put the last print

into the wash, as it was assumed that fixer would transfer to the water, and other prints.

 

I am not sure from your assembly line if you did that, but with HC it wouldn't normally

be a problem.

 

I wonder if you are not fixing enough? If there is still silver halide, then it is still light

sensitive. Though I have a tendency to turn on the lights fairly soon after prints are in

the fixer, probably sooner than is recommended, and have never had any problems.

(I suspect I have turned on the lights seconds after they went into the fixer, at

least for test strips.)

What is your hypo clear recipe? It could be doing more harm than good if it's something like the old Kodak HE-1 formula.

There's a reason for stop bath. Water isn't stop bath and causes the fixer to die an early death. Only time not to use an acid stop bath is with an alkaline fixer. Some decades ago there was a trend away from stop bath to water. People didn't like the smell or something. It was almost invariably a mistake.

I suspect the fixer- a bit more time won't hurt and/or get some fresh. Two-bath fixing is more effective- see Ilford data sheet.

Do you develop to near completion or pull the prints by inspection? Best to fix the development time to near completion, usually 1 minute absolute minimum.

Goes to show that something labeled an "archive" process can still go wrong!

Edited April 18, 2019 by conrad_hoffman

Also you aren't supposed to use acid stop bath with Diafine, but that doesn't apply to prints.

 

Yes, too many prints could kill the fixer.

 

OP didn't say rapid or regular fixer, but the time given is short for regular fixer.

 

I was trying to see the pattern in the yellowing, which looks non-uniform.

That could mean underfixing due to other prints slowing it down, or shading

light from still light sensitive prints.

 

I have found rapid fixer especially pH sensitive, so, yes, too much developer

carry-over could kill it. You can't judge clearing time the same way as film.

If you have a pH meter, or pH test paper, you could test it.

 

Refixing with fresh fixer might help.

I've never had or had access to a pH meter, but the data sheet does talk about it. IMHO, it's a good idea to read the data sheets for every chemical you use. Extra points if you also read the MSDS, but don't get too freaked out by it or you'll never use pyro or PPD.

Photo films and papers are comprised of silver salt crystals held in place by a binder (glue) of gelatin. Gelatin is chosen because it has low solubility in water, it is transparent, it is flexible, and it is permeable (fluids can easy enter and exit). In the case of papers, the emulsion (paraphernalia that holds the crystals) is applied to a primer coat. This is called “Baryta Coat”, clay like white base of barium sulfate. This is a whitener but more important it is a barrier that prevents the emulsion coat from penetrating into the paper which is likely wood pulp based. RC papers are further sealed by a film of fabricated resin (polyurethane). No matter how protected, fluids can and do enter the paper fibers at the cut edge of the print paper. Any of the fluids of the process that are wicked up by the paper must be amply removed, if not, staining will occur.

 

Both the standard fix and the rapid fix are sulfur based chemicals. If not removed, the sulfur combines with residual silver forming the yellowish compound, silver sulfide. Actually, silver sulfide is less reactive than the metallic silver image of the black & white process. Photographers often tone black & white prints using a sulfur based toner. This gives a warmer tone that many find attractive and if properly applied, and grant advanced archrival properties.

 

The developer is alkaline and the fixer is an acid. If excessive developer is carried over to the fix, the fixer's life is shortened. For this reason, an acid stop bath is preferred as it stops development in its tracks and neutralizes the alkalinity of residual developer that likely has infused into the wood pulp cells.

 

The fix is a solvent for undeveloped silver salts. These salts must be removed else they self-reduce to metallic silver and a halide. Halide is Swedish for salt maker. We are talking about the halogen family of elements, bromine, chlorine, and iodine. These are the three salt makers used in combination with silver to form a light sensitive emulsion.

 

After the fix we wash copiously to rid the paper of residual chemicals. It takes a good 30 minutes of washing for single weight and 60 minutes for double weight. RC paper washes quickly because the polyurethane coat protects, all but the edges from chemical entry. A wash agent promotes fast exit of residual chemicals.

 

Paper fix in 45 to 70 seconds in fresh rapid fixer. If the fix is further diluted from working strength or well used, fix time can double or triple. Photofinishers use two fix baths. The fist exhausts fast and is replaced by the second. A fresh fix is then placed in the second position. Prolonged fixing is discouraged. The desired silver image may come under attack, then the paper becomes more saturated with spent fixer making washing more difficult. A rinse agent is unnecessary if water is cheap and you can spare the extended time required to purge residual chemicals.

Edited April 18, 2019 by alan_marcus|2

I'd suspect the hypo clear. Never used the stuff for my own work, and never worked in a professional darkroom that used it either. Just wash the paper for 30 minutes, either in gently running water, or using several changes of fresh water.

 

Potassium permanganate will sequester hypo, but it leaves an orange residue behind, which is near impossible to get rid of.

 

What's your water supply like? It's just possible that iron contamination might cause yellowing, but it would have to be quite a few ppm of contaminant.

 

Also, quite honestly, unless you're going to glaze the fibre-base prints, there's little point in using FB paper, because the self glaze of RC paper looks better and gives better contrast IMO.

Edited April 18, 2019 by rodeo_joe|1

(snip)

 

Also, quite honestly, unless you're going to glaze the fibre-base prints, there's little point in using FB paper, because the self glaze of RC paper looks better and gives better contrast IMO.

 

Fifty years ago, we used fiber based paper because that is what there was. I mostly used SW paper, because it was cheaper and washed faster.

 

But now, fiber based paper is for special occasions. Maybe like using the fancy dished instead of the every day dishes,

makes a meal seem more special, though tastes the same.

 

(I now have some, mostly that was given to me by people closing down their darkrooms,

but I haven't used it much.)

 

When I was young, I had a "Kodak Blotter Roll":

 

Kodak Blotter Roll 11 1/2" x 6' Fiber Paper Darkroom Drying Tool - USED K09 • $24.95

 

which has one sheet of ordinary blotter paper, and one sheet of specially coated blotter

paper. You put the prints in facing the special paper, roll it up (which rolls emulsion side

out), and let them dry (usually overnight). The roll counters curl that they might otherwise

have, and usually come out close to flat. Between the blotter paper, there is a sheet of

corrugated paper to allow air flow. I don't have that one any more, though.

@glen_h, you forgot about the joys of print flattening solution and ferrotyping.

 

I don't know if this is still true, but some decades ago paper seemed to change. It used to be that you could store the stuff for years, even unrefrigerated, and it held up well. Later on, the image quality seemed to suffer after only a year or two at room temperature.

@glen_h, you forgot about the joys of print flattening solution and ferrotyping.

 

I don't know if this is still true, but some decades ago paper seemed to change. It used to be that you could store the stuff for years, even unrefrigerated, and it held up well. Later on, the image quality seemed to suffer after only a year or two at room temperature.

 

I did once have print flattening solution, but it was expensive, and the blotter roll could be reused.

Also, it never worked all that well.

 

As I understand it, some paper now has developer built-in to the emulsion.

That seems to shorten its life, especially warm.

 

I have a package of Polycontrast III that I was given unopened, and maybe five years old.

 

It has the unusual condition that if you develop unexposed sheets, they are gray with about a 1/4 inch

(not sharply defined) white border. I suspect that this is due to poor storage.

 

I have a package of Agfa paper that I suspect is over 60 years old, and seems to work fine.

 

Well, also newer papers are much faster than older ones.

I often have a hard time getting a short enough exposure for modern paper with small

prints, and have used neutral density (equal C, M, and Y color print filters). Faster usually

means shorter life for film, maybe paper, too.

Graded Agfa Brovira, I miss you.

So, a bit of experimenting:

 

Being a scientist, I have a hard time changing more than one thing at a time.

 

So, after reading the responses here, I made up a stop bath(citric acid, as glacial acetic makes me sick and I didn't particularly want to handle it at home). I did also swap out for fresh fixer, but the same as yesterday. After developing, I dropped the print in that until it no longer felt "slimy", then fixed/washed/cleared/washed as before. I brought the room lights up during the first wash, before hypo clear, and so far it's staying nice and white.

My first thought reading your post was under fixed or not washed long enough. I’m still thinking that’s the problem. I quit using stop bath long ago but when I was running a darkroom everyday I could get plenty of life from rapid fix 1:1 for about five minutes and 20 minutes washing and had no problems wth discoloring. All RC paper. There is one framed on my wall printed in 1977 that’s still perfect. Yeah, I’m that old.

 

Rick H.

I have negatives back to 1968 (5th grade), but maybe not prints that old.

 

Well, for one, I was much better at shooting and developing film than printing it.

Now I can scan it and post on FB, so my school friends can tag them.

Sounds like the problem is resolved. Just for fun, look up the number of 8x10 prints you can fix in whatever amount of fixer you use in a tray. That will be with stop bath. I figure the number is maybe half without. Bet it's not many.

As a totally unrelated note-

 

Someone commented on the apparent speed of modern papers. I've noticed that myself, and it's amazing how short exposure times can be.

 

The above print was what I'd consider a "correctly exposed" negative, and printing on a Beseler 45M at f/8(105mm f/4 lens, so two stops down from wide open) gave me a 4 second exposure time. This was an 8x10 from a 6x6 negative, but printing from probably a 4cmx5cm area of the negative to get the framing as I wanted. I ended up with a 4 second exposure time.

 

I printed another 8x10 from this same roll of film that was a bit more dense, but also not cropped as tightly. I ended up at 8 seconds on that one.

 

I have an old Ilford print meter. Basically, as best as I can figure with it, you put the "eye" on your easel then twist the knob on top until the green LED illuminates. The way I've been using it is to put the "eye" somewhere I want rendered mid-gray and using that as my base exposure, but then also take readings at several other places. In any case, I quit bothering, as it's way off. Instead, I've gone to an ancient Kodak "exposure meter" transparency, which has a pie chart sort of thing printing on it with varying amounts of density, and marked in exposure times from 2 seconds to 60 seconds. You lay it over a sheet of paper and expose for 60 seconds, then develop and see what "slice" looks best. If I look at it and decide that between two looks good, I'll split the difference. The great thing about it is that even though it's probably 30+ years old, it will still work with any type of paper as long as you follow the instructions.

I've got a pie too! My Beseler 23CII is way too bright so I use a Variac and meter on the line. The color temperature changes slightly, but not enough to affect paper grade significantly. I want my optimum exposure to be about 7-10 seconds so I have time to dodge and burn. The answer is not stopping the lens down as that introduces diffraction. It should be about 1-2 stops down from wide open for maximum image quality. You also want to have a heat absorbing glass if you don't use glass neg carriers (and who does?) Or a cold light, but I prefer condensers.

 

Side note- paper is funny stuff when it comes to additive exposures. Try to make a calibrated grey scale strip some time. The additive exposures will be way off what a single exposure would have yielded for any given patch. That's why doing test prints by uncovering more and more of the image has to be done as a continuous exposure.

Two things -- Photo paper blackens twice as fast as film! This is because we view negatives and slides by transmitted light, we view prints by reflected light. Light from an adjacent lamp plays on the finished print. This light traverses the emulsion, hits the white Baryta coat, reflects back and traverses the emulsion a second time on its way to our eye. In other words, 1 stop + exposure to photo paper = 2 stops worth of blackening. Also, as film and paper age, background radiation, heat and age begin the process of exposing the light sensitive crystals. In other words, they are threshold to becoming developable is nearer. Thus they need less light to be rendered developable. Stated differently, paper and film speed increases with age. This is contrary to what most believe but true!

As a totally unrelated note-

 

Someone commented on the apparent speed of modern papers. I've noticed that myself, and it's amazing how short exposure times can be.

 

 

(snip)

 

Instead, I've gone to an ancient Kodak "exposure meter" transparency, which has a pie chart sort of thing printing on it with varying amounts of density, and marked in exposure times from 2 seconds to 60 seconds. You lay it over a sheet of paper and expose for 60 seconds, then develop and see what "slice" looks best. If I look at it and decide that between two looks good, I'll split the difference. The great thing about it is that even though it's probably 30+ years old, it will still work with any type of paper as long as you follow the instructions.

 

There is "Kodak Projection print scale". I believe the one I still have is the one my grandfather gave me about 50 years ago.

 

(I think others make them, too.)

 

I use some exposure meter, and some the projection print scale.

Ben, your procedure has three potential problems: too-short stop bath after developing, too-short fixing, and too-short washing.

 

1. Instead of quickly rinsing the developed print under running water, I recommend immersing it for 30 seconds in a tray of acid stop bath with constant agitation. For many years I used Kodak Indicator Stop Bath, which is acetic acid, but it's smelly. Later I switched to citric acid (mixed from powder) because it's equally effective and odorless.

 

2. Fiber-based paper needs more fixing than resin-coated paper, as Alan Marcus noted. However, you can dramatically shorten the fixing time by using a "rapid fixer" (such as Ilford's) mixed at film strength, not the usual paper strength. This solution will fully fix a FB print in 30-60 seconds. Limiting the fix time to about 60 seconds will reduce the amount of fixer absorbed in the paper and require less washing.

 

3. Normally, as Alan noted, double-weight FB paper needs at least 60 minutes of washing. Rapid fixing as described above, followed by a water rinse and hypo clear, can reduce that time to 10-30 minutes, depending on the wash-water temperature and water hardness. For critical work, you can buy chemicals that test for residual silver (to confirm if the print is fully fixed) and for residual hypo (to test if the print is fully washed). I have performed both tests several times, confirming that the procedure described above is valid for double-weight FB paper.

 

It's also possible that your paper is outdated (expired), but the procedure I describe is recommended in any case.

Ben is probably too polite to point it out, but... in his first post he links to an Ilford procedure "when optimum permanence is needed..." It calls for 1 minute fixing (Ilford fixer at 1+4), then washing (stop bath is not specified), Ilford wash aid, and then more wasing, etc. Per Ben, he is following this Ilford-specified procedure EXCEPT that he is using his own made up "hypoclear" as opposed to the Ilford "wash aid."

 

In other words, he already seems to be (pretty much) following an Ilford-approved procedure.

 

I don't really know what the real problem is either. If I didn't know from past posts that he is a chemist then I would probably suspect a botched-up wash aid, perhaps using a wrong chemical with a similar-sounding name. But I doubt that Ben would do this, nor that he would be likely to mess up on a fixer dilution. So I don't see any obvious problem, although such a problem seemingly must exist. Perhaps, even, Ilford has made a typo on the website?

 

My own thoughts on the matter are that inadequate fixing is a prime suspect. Perhaps it IS a mixing error; perhaps the stock fixer had previously been dilution 1+4, then erroneously diluted again. Perhaps, even, it was a defective chemical, possibly due to age, from the supplier.

 

At any rate, if one has a hydrometer in that range it would be easy enough to check the specific gravity to verify the dilution (the base value is probably on an MSDS, OR one could make the assumption that it it would be nearly identical to a Kodak product, which have both the pH and sp gr values listed in a CIS document (I can find the CIS number, if needed).

 

It's also easy enough to test for an approximate clearing time with the paper in use. Here's a version of the method that can be done in room light: take a strip of the paper and put several "distance marks" on it, perhaps they are notches or punched holes. Next, immerse the paper, up to the first mark, into the fixer, wiggling it around for agitation. After 5 or 10 seconds (keeping track of the time) immerse to the next mark, and so on. At the end of the test immediately immerse into water to rinse out the bulk of the fixer, halting the fixing stage as quickly as you can. You now have a strip of exposed paper with some of the silver halide already removed via fixing. Next immerse the entire strip in developer (use a small sample, as it should be discarded afterwards). All of the remaining silver halide should now develop as black, with the completely fixed steps showing as white. So you can say, oh, the fixing seems to be visually complete by such-and-such number of seconds. (The first part into the fixer had the maximum fix time, each successive step has the timed increments subtracted.)

 

Now, I just explained the test so as to be more understandable, but it's better to mimic the actual process for more accurate results. So ideally you would start out by "developing" the unexposed paper in the dark. Rinse or stop, or whatever you normally do, then do the stepped, timed fixing stages under a safelight. Then into a water wash to stop the fixing. Now the room lights can be turned on to expose the remaining silver halide, and finally the test strip can be developed in room light. The evaluation is the same - the first completely white step shows (approximately) the "clearing time." Just as with a film test, you want to fix for at least twice the clearing time.

 

Personally, if I were planning to use this Ilford method for serious work, I would be real bothered by the yellowing, and would want to nail down an explanation (or abandon the method). On the assumption that it might be due to too little fixing (assuming that I didn't find a defect in the fixer itself), I'd probably do some tests with REDUCED fixer time, expecting to aggravate the yellowing condition, just as a verification that the fixing time was marginal. Perhaps some extended fix time tests to "prove" that the problem never occurs after this.

 

Another possibility, suggested by rodeo_joe (post #8) is that something may be wrong with the hypo clear, possibly even its formulation. Thiosulfate (as in the fixer) is known to decompose at pH values below the low 4s range. (I have no idea how fast, never having played with this.) Perhaps some sort of hypo clear error, either in the formula or in the mixing, has produced such a low pH, resulting in a sulfur precipitate from residual thiosulfate. Without a pH meter in hand, one might try putting a few drops of fixer directly into the hypo clear to see if it decomposes (this should NEVER happen in a "traditional" sulfite/bisulfite wasing aid)?

 

Ps, I can't imagine that the pH of the fixer itself would be an issue. It's sometimes said on the internet that this can be a problem, but the standard rapid fixer components - ammonium thiosulfate and sodium sulfite (sometimes with bisulfite) - are used in the general pH range of the low 4s (compatible with alum hardener) up to about pH 7 (C-41 "standard" fixers). So I don't think that there is any problem here aside from the objectionable smell at the pH extremes.

 

Anyway, just some thoughts on the situation. Sorry for getting so wordy.

I typically print on FB Paper, and have never had the problem of the OP..... fingers crossed.

I also "make" my own wash aid.

I simply use one of those plastic spoons, like you would get from a fast food store, and dump that much Sodium Sulfite into a liter of water.

I have been doing that for several years with no known troubles. Are my amounts enough to make what most people would call Hypo-Clear.?

Thank You

I used to use a running water rinse between developer and fixer. Despite thinking that my rinse was adequate, it wasn't sometimes, and brown stains appeared. Now I use an acid stop and the problem has never reappeared.