One minute of fixing is enough!

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In a reply to one post there was a credo that one minute would not suffice for fixing. I think I have got some arguments and evidence sowing that a minute is enough:

1) As one post stated, I don't think any reputable paper manufacturer would suggest a processing method that would ruin images on his paper. Why should he?

2) Normally, we assume that it takes a new solution 15 seconds to penetrate the emulsion and at least start working. (That is the time usually suggested for the stop bath by many sources.)

3) The fixing speed (that was also mentioned in one post) depends largely on the fixing agent, its concentration and the degree to which the bath has already been used, i.e. its silver content. The sodium salt used widely some 20 years ago is slow. You can see that from the suggestion to soak your prints in it for 10 minutes. Rapid fixer is based on ammonium salt. This is rapid indeed and allows fixing times of about two minutes (Ilford Hypam at paper strength) or one minute (Ilford Hypam at film strength).

For the latter, I have some evidence: I prefer the two-baths fixing method, i.e. I fix for 30 s in the first bath (Ilford Hypam at film strength) and then for a further 30 s in a second fixing bath (also Ilford Hypam at film strength). Those two baths are identified as fix #1 and #2 to avoid confusing them. After some 20 to 30 8 x 10 prints I replace the first bath by the second and mix the second one fresh. (The first fixer can still be used for films as long as its silver remains below 5 g/litre.) The effect is this: The first bath does most of the 'dirty work', the second just making sure that no residual undeveloped silver remains in the emulsion. After reading the post, I tested my fixers for silver, having processed a little more than 30 8 x 10 prints in the way described above. The result is this: The first bath contained between 1.5 and 2 g of silver per litre, and the second one less than the detection threshold of the test (0,5 g/litre). This is only a different way of saying that most of the undeveloped silver goes from the emulsion into the fixer within 30 s!

Keeping your fixing time that short allows you to keep washing time short, too, thus saving a lot of water and time, because washing out the fixing agent is only hard when the paper base is full of it.

-- Thomas Wollstein (thomas_wollstein@web.de), July 28, 1999

Answers

I have used the method you describe for a number of years. I thought this was common knowledge.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), July 28, 1999.

It should be. Its been on the instruction sheet in every box or bag of Ilford paper for the last 15+ years.

-- Gene Crumpler (nikonguy@worldnet.att.net), July 28, 1999.

If one minute of fixing in paper fix is enough, then why do you do them both at film strength?

This was never mentioned in the earlier conversation, in which I based my views upon fixer that is mixed for prints, not negatives. To say that prints only need one minute of fix but not to reveal that this was done at negative fixer strength is a bit misleading don't you think? And on top of that you do a two fix method (which I also do), so your method done at paper fix strength (which was what we were supposedly talking about since we were talking about prints) equals a 4 minute fix time total does it not? This is much more in line with what I was talking about.

Would you agree?

-- mark lindsey (lindseygraves@msn.com), July 29, 1999.


sorry, too late at night, your calculations equal a 2 minute fix in paper fixer not 4, never the less the argument still holds true

-- mark lindsey (lindseygraves@msn.com), July 29, 1999.

My understanding is that the Ilford technique always specified fixer at film strength--the idea being to use a very strong fix for a limited time, thereby reducing the possibility of the fixer penetrating deeply into the fiber of the paper where it is difficult to wash out.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), July 29, 1999.


Mark,

as Ed Buffaloe stated, the method is not new. I do not understand what you mean by calculations that should result in four minutes.

I think however, I can answer your question as to why two baths should be used. The use of two baths has the advantage of removing the silver halide complex much more thoroughly from the emulsion than with one bath *in the same time*. In the first fixer, there is still enough active fixing agent to dissolve the silver halides, but only a small gradient between the emulsion and the bath because there is a fair amount of silver in the first bath. Diffusion is an exponential process and its speed depends on the concentration gradient. This means that the largest portion of the dissolved silver halides leaves fairly quickly, but it takes extremely long to remove the tiny little remainder. That is where the second bath comes in. Most of the silver remains in the first bath, so the second one is essentially free of silver (see also my tests). Moving the print from bath #1 to bath #2 means abruptly increasing the gradient between emulsion and bath thus accelerating the diffusion of the remaining unwanted stuff.

-- Thomas Wollstein (thomas_wollstein@web.de), July 29, 1999.


ok, do you see an improvement in the quality of your photos using the 1min two-bath method over say a 15 minute single bath? or a 3min single bath or any difference at all other than saving water and wasting fix? water is cheap around here...fix is still 8 bucks a gallon! You guys are splitting hairs in the single-most unimportant step of the process..... Print fixing....honestly I don't want to "time" my prints in one fix bath or two......I use a two bath method too...I splash a little fix into the quick rinse water tray! voooleeee! hee heee works as a stop bath too! Here's a confession...right after I process film...i dump the used fix into my trays...oops I feel dirty...absolve me quickly with a abbreviated rinse! another confession sometimes if someone calls me on the phone or I have to go to the potty, the prints get fixed for a half hour! ooopss forgive me Thomas for I have sinned, it's been six seconds since my last confession! Fellas you are sucking all the fun out of the hobby! I'd like to confess some cardinal sins that I'm not proud of from my photo-j days too but they'd make you scientists puke!

-- trib (linhof6@hotmail.com), July 29, 1999.

Thomas, I know why a two fixer bath is good, I've been in this for almost 20 years. Nor did I ask for an explanation of it.

Didn't you read the follow up posting?

I corrected myself in that the calculation would equal a 2 min. fix total (film strength=30 sec./paper strength=1 min., therefore if you fix prints for 30 sec. in film strength fix it equals a one min. fix in paper strength, fix x 2 bath fix= a total of 2 min. in fix, correct?

Don't you think that film strength fixer will penetrate paper twice as fast as paper strength fixer? it must if it fixes twice as fast.

so wouldn't the idea that a shorter fix time be moot simply because you shorten the time but strengthen the concentration?

-- mark lindsey (lindseygraves@msn.com), July 29, 1999.


That last line should read,"so wouldn't the idea that a shorter fix time helps be moot simply because you shorten the time but strengthen the concentration?"

Thomas, one more thing that concerns me is the fact that as the amount of time a print is in a solution shortens, so goes up the margin of error, in other words, if you are off 10 seconds when doing a 1 min process you have erred by 16.5%, if you are off 10 seconds from a 6 minute process you have erred by about 2.7%. Now I know that for most of us who do our own darkroom work that 10 seconds can be a lifetime and can't imagine being that far off at any time, but why let yourself be open to it?

-- mark lindsey (lindseygraves@msn.com), July 29, 1999.


trib (is that a name?)

In fact, your statement "You scientists take all the fun out of the hobby!" may be true from your side. Still, to me, in photography technical and scientific aspects are part of the pleasure, and part of what I like about photography. BTW, no one forces you to work acc. to the method described, nor to read any posts on it. Also, why should I puke about your way of processing prints? Let me enjoy my way of doing it, you do it your way!

Mark

To answer the last question first: The margin for error is certainly narrower. You have to weigh all the advantages and drawbacks of the method acc. to your taste and make a decision. I have made mine.

As for the effect of doubling the fixer concentration on print penetration: Soaking the print for the long times required with the old sodium salts (some 10 minutes) will lead to the print getting to equilibrium with the solution, i.e. becoming soaked with fixer solution of the same concentration as the bath. The short fixing times, however, open up the possibility of keeping the print away from equilibrium, i.e. of having the fixer quickly penetrate the emulsion and do its work while not soaking the paper base too strongly. In this case, as the process is exponential, the shorter the time, the better. I would have to run some tests to show whether there is a big difference in washing time required between two minutes at concentratin x and one minute at concentration 2x, but I do trust Ilford to have good reasons for recommending the method.

Your final question: Why bother? I have two reasons: First, I was brought up to give quite some consideration to environmental-protection aspects, and saving water is one of these. Second, when I go to the darkroom in the evening, I know my time is limited because I have to get up early in the morning. After I have completed the last print of the evening, I have to stay up to wash the prints and then take them out of the washer. If the washing takes half an hour less, I can use that half hour for printing instead of waiting for the washing to be complete. So environment and comfort work together here to convince me.

-- Thomas Wollstein (thomas_wollstein@web.de), July 30, 1999.



Thomas hit it on the head. It's a time thing for us darkroom workers who only have short periods of time to spend in the darkroom.

-- Gene Crumpler (nikonguy@worldnet.att.net), July 30, 1999.

Trib, you have indeed sinned, and if you don't mend your ways you will end up in an unventilated darkroom in an obscure corner of hell breathing brown toner fumes and waiting for your prints to fix forever. Seriously, though, the reason we split hairs over fixing and washing is to try to get the most archival prints possible. If you're not interested, please ignore us.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), July 30, 1999.

Thomas...does it matter (name)? and why would you bother if over- fixing is close to impossible what's the difference ....you know... the end result! Do you use a hypo-remover? You have a powerful and scientific understanding for man's a impact on the earth! You may be overestimating that impact but stick to yer guns!

Ed and Gene....slow down! enjoy your time alone in the dark! If life is rush, rush, rush then why carry that over to the darkroom? I really can't believe that a photographer (maybe a scientist but never an anxious photog) would care to calculate remnant silvers in grams per litre before replacing it....

Thomas, I'm beginning to think that higher math is chewing up what little time you have to spend in the darkroom...I wonder what kind of street shooter or candid shooter you'd make? I just bet you'd miss alot of shots if you persist in pulling out the slide-rule to calculate your dof!

-- trib (linhof6@hotmail.com), July 30, 1999.


May I suggest that this thread is taking a more philosophical turn, and perhaps should be continued on a new thread, something like "Making Priorities"? There is merit to both arguments--the careful scientific approach vs. the more spontaneous method.

One observation: the late Peter Moore, who I had the priveledge to work with at Modern Photography, fit the profile of the meticulous photographer whose testing procedures were beyond reproach (which often meant his missing publication deadlines), and who could produce technically perfect images...and yet, he loved nothing more than to grab a beat up old Leica M2 and go out during lunchtime to photograph the street life in NYC, then go into the darkroom and gang-print the negs on RC paper! There's a lesson to be learned here, I think.

Or, as my wise friend Sam often says: Everything in moderation...including moderation.

-- Mason Resnick (bwworld@mindspring.com), July 30, 1999.


"Everything in moderation" I use RC paper to save time and effort. I'm not picky about archival. I do two bath fixing with paper strength rapid fixer. I get more use out of the fixer; less waste. I use Edwal Hypo Check. Prints stay about 2-3 minutes in each fix bath, I don't explicitly time them. I put prints in a 5th tray with water to hold for batch washing. Basically, I take it easy.

-- Tim Brown (brownt@ase.com), July 31, 1999.


There are many good reasons to keep the fixing time as short as possible. The developer is exhausted through both use and oxidation. Both cause by products that are trapped in the emulsion and carried over to the fixer through the stop bath. The stop bath only changes the PH of the print from alkaline to acid so that it matches the fixer in PH (acid versus alkaline), and stops the developer rapidly to cut down on the amount of by-products carried over into the fixer.

As the fixing bath is used, more and more of the used developer is carried over into the fixer and the acidity of the bath falls off due to the developer oxidation products. Silver oxide, present is small amounts, builds up in the fixer and can cause dichoic fog. Among other by-products are the complex argentothiosulphates which can mordant (chemically combine) with the paper base as insoluable compounds. The longer the paper is left in the fixer, the more the compounds combine with the paper base. No amount of after treatment or washing will get these mordant compounds out of the paper base. This is why resin coated paper doesn't need to washed as long. There are no compounds combined with the paper base.

The short, double strength ammonium thiosulphate fixing procedure has been formulated to avoid long soaking times specifically to preclude the formation of insoluable compounds that attach to the paper base due to prolonged fixing times.

-- franki wango (MrWango@worldnet.att.net), August 06, 1999.


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