Using Kodak Rapid Fixer

[david b]

Okay this is a really silly question.

I have a friend who works in a photo store and ordered the wrong size fixer. So to help her out, I bought the 5 gallon (19 liters) container from her. It did not come with the hardener which is fine with me.

My question is, how do I mix a working solution for film and paper, 1 liter at a time?

thanks.

 

[unregistered]

1:3 for film and 1:7 for paper.

http://www.kodak.com/global/en/professional/products/chemistry/bwPaperProcessing/rapidFixer.jhtml

Click on the 2 links to the left. 1 for paper and 1 for film.

 

[Loose Gravel]

I mix them them both 1:3 and use the Ilford recommended times for fixing.

Good thing you didn't get the other part. Chances are you didn't want the hardner anyway and it is the 'toxic waste' part and expensive to mail. I was buying the gallon size and taking the hardner out and handing it to the cashier so I didn't have to dispose of it. Now I order the 5 gallons and you don't have to get the hardner at all. A better deal.

 

[unregistered]

I mix them them both 1:3 and use the Ilford recommended times for fixing.

Good thing you didn't get the other part. Chances are you didn't want the hardner anyway and it is the 'toxic waste' part and expensive to mail. I was buying the gallon size and taking the hardner out and handing it to the cashier so I didn't have to dispose of it. Now I order the 5 gallons and you don't have to get the hardner at all. A better deal.

you are over fixing your paper. Although since you are using Ilfords time of what, 1 or 2 minutes in the universal fixer, compared to 5 for the kodak, maybe you aren't.

 

[david b]

I've used this fix in the past and would do film for 5 minutes. How long should I fix the paper for (rc and fiber)? The Kodak times seem excessive.

 

[Loose Gravel]

Paper for 1 min and film for 2-4 min. Those are my times.

I wish I were over fixing (just kidding)...I haven't printed in way toooooo long. Taking too many pix to print. I have a hard time balancing the take/print thing.

 

[Curt]

Im in the same boat, if I stopped taking pictures I could spend the rest of my life in the darkroom printing. How do people get into this situation? Is there a tendency to over shoot or a fear of not doing enough shooting?

Curt

 

[Loose Gravel]

Curt

I always figured if I could shoot, I should. When I can't walk anymore, I could still print. I guess I've taken it to extremes. I am trying to catch up, though. I'm sorting the negs, making sure there is a contact sheet for every neg, get the negs in order and all. I'm probably 10 years behind on that. I have some of the proof sheets, but I don't know which ones. I also owe favors in the form of prints to people for years. Now I tell people, when they ask, that they will never see a copy of a pic. I have resolved to myself that this is the year to catch up in that department, too. Time to move on.

 

[unregistered]

Paper for 1 min and film for 2-4 min. Those are my times.

I wish I were over fixing (just kidding)...I haven't printed in way toooooo long. Taking too many pix to print. I have a hard time balancing the take/print thing.

Those times are wrong. They are Ilfords Universal Rapid fix times...a formula different from Kodak's. If Kodak tells you 5 to 10 minutes for fiber, it is obvious that they have tested the solution with paper and have found that that time is needed to properly fix a print.

Why someone would argue with that is beyond me.

But there is no accounting for the failure to understand the photographic principles involved.

Sheesh

 

[Loose Gravel]

Near as I can tell, Ilford Uni RF and Kodak RF are nearly identical if the Kodak hardner is not added (except Ilford's tolerances are very crude).

I'm not arguing with anybody, I'm just doing it.

What are the photo principles that I'm missing?, do tell.

Kodak
Weight % Components (CAS-No.)
40 - 45 Water (7732-18-5)
42 Ammonium thiosulphate (7783-18-8)
5 - 10 Sodium acetate (127-09-3)
1 - 5 Boric acid (10043-35-3)
1 - 5 Ammonium sulphite (10196-04-0)
1 - 5 Acetic acid (64-19-7)
< 1 Sodium bisulphite (7631-90-5)

Ilford
INGREDIENT NAME: CAS No.: CONTENTS : EPA RQ: TPQ:
SODIUM SULPHITE 7757-83-7 1-5 %
SODIUM ACETATE 127-09-3 1-5 %
AMMONIUM THIOSULPHATE 7783-18-8 30-60 %
BORIC ACID 10043-35-3 1-5 %
ACETIC ACID 64-19-7 1-5 %

 

[dancqu]

...except Ilford's tolerances are very crude...
What are the photo principles that I'm missing?, do tell.

Ilford is not telling us very much.

Missing or not I'll mention dilution. BTW, Ilford was 1:3 and
1:7 and is now 1:4 and 1:9. But almost any dilution will work
as long as enough chemistry is included, and work quickly.

I and a few others use 1:24 one-shot for film; 20ml of
concentrate. The same dilution, half the volume, will work
for FB 8x10s. For paper, archival results may be had with
a single, very dilute, one-shot fix. Dan

 

[Ryuji]

About the dilution of fixer.

In terms of speed of fixation, the optimal concentration is about 120-150g/L of ammonium thiosulfate. However, acceptable fixation may be obtained in 100-200g/L range for film emulsions. Chlorobromide emulsions may be fixed at a bit lower side of this range as well.

Most rapid fixer concentrate products contain 600g or less of ammonium thiosulfate in a liter of concentrate stock, because 600g/L is the practical max concentration. For example, the fixer product I designed, Silvergrain Clearfix (an alkaline rapid fix), contains this maximum amount of ammonium thiosulfate. If you use at the directed 1+3 dilution, you'll get a working solution containing 150g/L ammonium thiosulfate. Even if the fixer gets diluted by carryover of stop bath or rinse water, the fixer remains strong enough to ensure good fixation. If it is diluted 1+4, the working solution will be 120g/L, which is close to "film strength" recommended by Kodak and Ilford.

Because of effort to cut costs and desire to advertise higher concentration, some manufacturers put significantly less 60% ammonium thiosulfate and/or recommend greater dilution to fall in the low end of the usable range. In terms of marketing and commercialism, that may be a good idea, but in my view, it's an unwise approach.

If you use Ilford's Archival Sequence, it's important to use 120-150g/L concentration for one minute. Weaker fixer runs risk of insufficient fixation with 1 min fix, and longer fixing time will require significantly longer washing time to achieve the same residual thiosulfate level (I've tested these things with several materials and several conditions).

Kodak and a few other fixers (such as Edwal Quick Fix) recommend 1+7 dilution for paper. This is more economical if longer fixing time is tolerated, such as small volume processing of RC prints.

As Loose Gravel discussed above, Kodak Rapid Fix (or Edwal Quick Fix for that matter) without hardener may be used in place of Ilford Rapid Fix in Ilford sequence, but at 1+3 or 1+4 dilution.

So, what is the difference between 1+3 and 1+4 dilution? With Clearfix, if you benchmark time to fix a fast film between these dilutions, you may see a small advantage of 1+3. The higher concentration is also a safer choice if you are not very meticulous in removing excess stop bath/rinse water, because even if the fixer gets diluted, it's well within optimal range. But if you are a careful and cost-sensitive darkroom worker, you might want to use an unofficial dilution of 1+4.

 

[jonnyboy]

About the dilution of fixer.

Kodak and a few other fixers (such as Edwal Quick Fix) recommend 1+7 dilution for paper. This is more economical if longer fixing time is tolerated, such as small volume processing of RC prints..

I may be somewhat dense, but could you explain any rationalization for using a rapid-fixer for RC prints? Are folks really in that much of a hurry? In the 30+ years I have been printing B&W RC, I have never even thought of using rapid-fixers. What can possibly be gained?

Jon

 

[Ryuji]

I use Clearfix 1+3 for film, RC and FB. Speed gain is important for me when I'm printing a lot. Rapid fixer also washes out faster.

Another thing is that, I generally prefer short wet time for both RC and FB. Since I tone prints, which takes additional 5 minutes, I'd rather use rapid fix. To make prints that dry flat, minimizing wet time is one of the first step.

But there is nothing wrong with non-rapid fixers for RC prints if you prefer. Non-rapid fixers are a bit better when released to the environment, since rapid fix contains a lot of biologically available nitrogen source.

 

[jonnyboy]

I use Clearfix 1+3 for film, RC and FB. Speed gain is important for me when I'm printing a lot. Rapid fixer also washes out faster.

Another thing is that, I generally prefer short wet time for both RC and FB. Since I tone prints, which takes additional 5 minutes, I'd rather use rapid fix.

Yeah, I quite understand the use with FB and film, it's just that I couldn't wrap my small brain around using it with RC prints. Ah well, to each his own.

Jon