Mixing your own darkroom chemicals - the starter kit

[Keith Tapscott.]

Interesting, that's all from this page on my website.

Ian

I was thinking that myself.

 

[koraks]

This will bring the chemists out in force.

Thanks; that may have been the post I read when I made my remarks about sulfite vs. other means.
One thing I don't necessarily agree with (here we go) is this:

There are several studies that investigated the washing accelerating properties of alkaline bath. For example, Crabtree compared sodium hydroxide, ammonium hydroxide, sodium carbonate, Kodalk (sodium metaborate), and distilled water. This result was probably valid at that time, but the factors involved in washing property of fixed film and paper are somewhat different nowadays, because today's emulsions are highly hardened during manufacturing and use of hardener is becoming uncommon in manual processing. Therefore, it's probably not very meaningful to discuss those methods in detail. If there is anything worthy of noting, it is probably that Crabtree found that ammonium hydroxide was most effective of those.

In some cases, you can actually see visually what happens; e.g. when washing out dichromate stain from a gelatin emulsion. This is a slow process when using tap water, but tap water with a little carbonate added to it speeds this up nearly infinitely. From a theoretical viewpoint, I also don't agree with the notion that the fact gelatin emulsions are more hardened today would somehow render an alkaline wash aid ineffective. A hardened emulsion still swells more in an alkaline environment than a pH neutral environment. As such, it will still speed up washing of the emulsion. I emphasize the latter bit because I don't know what, if any, effect there is on wash effectiveness of the fiber base of FB papers.

 

[Ian Grant]

As such, it will still speed up washing of the emulsion. I emphasize the latter bit because I don't know what, if any, effect there is on wash effectiveness of the fiber base of FB papers.

At the time Crabtree did this research all papers were fibre based, and it was known that some of the semi-soluble Silver Thiosulphate intermediary complexes formed weak bonds with the cellulose in the paper base.

Levenson's research showed that when Aluminium based Sulphate hardeners were used in Acid fixers it was difficult to remove all traces of Thiosulphate bound to gelatin in the emulsion. So an HCA/wash aid solves the problem.

This s one of the reasons Ilford don't recommend Hardening Fixers, and they only recommend the use of Wash Aid with FB papers. There's another difference. Agfa suggest the 1% Sodium Carbonate bath immediately after fixing, whereas Ilford suggest 5 minutes water wash after fixing and the wash aid bath.

Ian

 

[Chuck_P]

I may have missed it but I skimmed through the thread but didn't see what I was wanting to know.....................what is an acceptable water ph when mixing your own darkroom chemicals from the tap? A friend is coming to measure the ph of my tap water as she has a meter specifically for that in the line of work that she does. I know mine is not going to be totally neutral at 7 but is there an acceptable range within neutral that would generally not affect the activity of most chemicals we use? I am just getting into mixing my own chemicals and I know all the advice is to use distilled water, and I can, but I am just curious. Thanks.

 

[koraks]

what is an acceptable water ph when mixing your own darkroom chemicals from the tap?

Doesn't matter. The buffering capacity of tap water is virtually zero.
The things in tap water you should/might/could be concerned about would be stuff like iron ions. Commercial photo chemistry contains sequestering agents to capture those and prevent them from wreaking havoc. DIY chemistry that omits these may have a shorter lifespan and may in some cases only be used once if reliability is required (e.g. ascorbate-based developers). And provided they're mixed with tap water.

Long story short - ignore the pH of your tap water. It's not a relevant piece of information.

 

[Chuck_P]

Doesn't matter. The buffering capacity of tap water is virtually zero.
The things in tap water you should/might/could be concerned about would be stuff like iron ions. Commercial photo chemistry contains sequestering agents to capture those and prevent them from wreaking havoc. DIY chemistry that omits these may have a shorter lifespan and may in some cases only be used once if reliability is required (e.g. ascorbate-based developers). And provided they're mixed with tap water.

Long story short - ignore the pH of your tap water. It's not a relevant piece of information.

Got it, thanks.

 

[Augustus Caesar]

Borax +
Boric Acid
Elon/Metol +
Hydroquinone +
Phenidone +
Potassium Bromide +
Potassium Carbonate (anhydrous)
Potassium Iodide
Sodium Bisulphite
Sodium Carbonate +
Sodium Bicarbonate
Sodium Citrate
Sodium Hydroxide
Sodium Metabisulfite
Sodium Metaborate
Sodium Sulphite +


That should get you started. The items with plus signs (+) are the ones most used in developers.

 

[Ian Grant]

You don't need Sodium Bisuphite, it's low grade Sodium Metabisulphite.

Ian

 

[koraks]

Well, you also don't need citrate, because (1) it's rarely used in developers and (2) if so, it can easily be made in situ using citric acid.
Boric acid is likewise not something particularly necessary. And out of the metaborate/borax pair, either will do just fine.
Potassium iodide is likewise not a very common ingredient and especially when doing B&W work, it's easy to avoid its necessity. But it's cheap, so what gives.
Potassium carbonate is nice if you need to make something concentrated; in all other instances, sodium carbonate will suffice.

On the other hand, it's convenient to have some form of acid on hand; acetic and/or citric acid make good sense.

But, you know...

With lists like these there's always the question what should or shouldn't be included. It's an endless discussion.

 

[Augustus Caesar]

You don't need Sodium Bisuphite, it's low grade Sodium Metabisulphite.

Ian

You'll note I designated the most important chemicals with +. Sodium Metabisulphite is used in FX-21.

 

[Augustus Caesar]

Well, you also don't need citrate, because (1) it's rarely used in developers and (2) if so, it can easily be made in situ using citric acid.
Boric acid is likewise not something particularly necessary. And out of the metaborate/borax pair, either will do just fine.
Potassium iodide is likewise not a very common ingredient and especially when doing B&W work, it's easy to avoid its necessity. But it's cheap, so what gives.
Potassium carbonate is nice if you need to make something concentrated; in all other instances, sodium carbonate will suffice.

On the other hand, it's convenient to have some form of acid on hand; acetic and/or citric acid make good sense.

But, you know...

Some of these are used in FX-21.

 

[dpurdy]

One thing I don't understand is the lack of PH monitoring. We all know that the PH is important enough that sometimes minute amounts of chemicals are included in formulas just for changes in PH. Yet we all have different water, I would guess that most people use tap water, that varies from place to place and time of year to time of year. For my beer brewing I have to have precise PH and a digital PH meter. I find that very tiny amounts of various chemicals make very large PH shifts. So why doesn't every formula give a target PH and why isn't a good PH meter an essential tool?

 

[Milpool]

One thing I don't understand is the lack of PH monitoring. We all know that the PH is important enough that sometimes minute amounts of chemicals are included in formulas just for changes in PH. Yet we all have different water, I would guess that most people use tap water, that varies from place to place and time of year to time of year. For my beer brewing I have to have precise PH and a digital PH meter. I find that very tiny amounts of various chemicals make very large PH shifts. So why doesn't every formula give a target PH and why isn't a good PH meter an essential tool?

pH targets/ranges are indicated for some formulas. However for the most part if you are using reasonably good/fresh compounds, mix photographic formulas as directed, and follow the capacity and storage instructions/guidelines, pH shouldn’t generally be a problem.

While small amounts of certain compounds can significantly affect pH, these are almost never called for, and in most formulas the primary pH-determining compounds are present in amounts of at least a gram or a few grams, which means small errors measuring weights etc. won’t be a big deal.

Water pH is a non-issue as whatever mild alkalinity or acidity it has is totally overwhelmed by the other constituents. Water has essentially no buffering strength.

If you’re attempting to modify formulas or invent your own, then yes a way of measuring or at least approximating pH is a good idea.

 

[Ben Hutcherson]

One thing I don't understand is the lack of PH monitoring. We all know that the PH is important enough that sometimes minute amounts of chemicals are included in formulas just for changes in PH. Yet we all have different water, I would guess that most people use tap water, that varies from place to place and time of year to time of year. For my beer brewing I have to have precise PH and a digital PH meter. I find that very tiny amounts of various chemicals make very large PH shifts. So why doesn't every formula give a target PH and why isn't a good PH meter an essential tool?

If you look at a lot of developer formulae, you will see that some sort of buffer system exists in many of them.

Buffers exists so that "minute amounts" of any substance won't affect the pH appreciably.

The closest I've monitored pH has been when mixing ECN-2 chemistry, and I've found that following Kodak's published recipes I land on a pH essentially dead on what Kodak says it should be. Granted I've primarily used DI(RO) water, but have found that tap water doesn't change it much. The ECN-2 developer uses a carbonate-bicarbonate buffer. From my recollection, the first batch I made came it at 10.27 on the pH meter I was using(calibrated an hour before use at pH 7 and 10, and periodically checked). Kodak specifies 10.25+/- .05 for that developer.

Generally any water source, whether tap or purified(by whatever means most fitting) will have so little buffering capacity that the components you're adding will influence the pH much more so than anything that was in the water to start. Most published formulae also specify a chelating agent, which will take care of anything that could be problematic.

 

[Carnie Bob]

One thing which would be advantageous to me but it seems impractical is to mix my Rapid Fix, We use a lot of Hypam here and 5 liter bottles go through our facility
quite quickly. Years ago I had a technician working with me who decided mixing rapid fix was the idea for us from scratch.. I seem to remember it being lengthly and about the same cost.
Not sure if others here mix their Dev (Multigrade) and Fix ( Hypam) but would be interesting to here your thoughts on this.

 

[Milpool]

One thing which would be advantageous to me but it seems impractical is to mix my Rapid Fix, We use a lot of Hypam here and 5 liter bottles go through our facility
quite quickly. Years ago I had a technician working with me who decided mixing rapid fix was the idea for us from scratch.. I seem to remember it being lengthly and about the same cost.
Not sure if others here mix their Dev (Multigrade) and Fix ( Hypam) but would be interesting to here your thoughts on this.

Scratch-mixing a rapid fixer usually doesn’t save you much unless you have an inexpensive source for the main ingredient - ammonium thiosulfate (typically available as a 60% aqueous solution). There are workarounds (sodium thiosulfate + ammonium chloride) but that’s not quite as good. Overall you’re probably better off just buying the Ilford product. It may or may not be more economical to buy a neutral pH rapid fixer such as Kodak Flexicolor if you want the concentrate to have a longer shelf life but this probably isn’t worth it if you tend to use up the fixer on a regular basis.

Developers can sometimes make sense to scratch mix if someone wants to do the math. If you are using Ilford Multigrade developer any number of standard print developers (D-72 etc etc) will do the same thing but I don’t know if you save money or not. It will depend on how much printing you do.

 

[koraks]

Not sure if others here mix their Dev (Multigrade) and Fix ( Hypam) but would be interesting to here your thoughts on this.

Developer - yes. I mostly use ID62 for B&W prints, pyrocat and instant mytol for film and ECN2 developer for Kodak Vision3 cine film. But I'm a tinkerer, so scratch mixing developers is kind of fun to me.
For fixer I don't see the point in DIY-ing it; as you've observed, the cost benefit is near zero, so you end up actually saving time by buying the commercial product.

 

[MattKing]

One thing which would be advantageous to me but it seems impractical is to mix my Rapid Fix, We use a lot of Hypam here and 5 liter bottles go through our facility
quite quickly. Years ago I had a technician working with me who decided mixing rapid fix was the idea for us from scratch.. I seem to remember it being lengthly and about the same cost.
Not sure if others here mix their Dev (Multigrade) and Fix ( Hypam) but would be interesting to here your thoughts on this.

Bob,
If you can find a Canadian source, this might be another option for you:
https://kodak.photosys.com/collecti...ixer-solution-part-a-to-make-20l-cat-105-9914

 

[Ben Hutcherson]

Here's some quick math on DIY vs. commercial fixer

A bottle of Kodak Rapid fixer is $15 USD, aproximately. Diluted to 1:4 working strength, this gives 3.8L(1 gallon) of working solution for film.

Just using this formula for Kodak F-34 Rapid Fixer, which I don't know how similar this is to the commercial "professional rapid fixer", you see that you need the following to make 1L working solution(I'm assuming this is a film strength fixer, or 1:4 from concentrate, not 1:9 for paper. The formula is identical or nearly so to Kodak's published fixer in the ECN-2 process manual) :

185mL 60% Ammonium Thiosulfate
10g sodium sulfite(anhydrous)
8.4g Sodium metabisulfite

To make that into a 3.8L formula, those volumes turn into

703mL thiosulfate
38g sulfite
32g metabisulfite

Looking at Artcraft, I see the following current prices:

1qt(946mL) Ammonium Thiosulfate $9.18
1lb(450g) Sodium Sulfite $6.18
1lb(450g) Sodium Metabisulfite $7.29

That does add up to more than the bottle of Kodak concentrate, but you'll use tiny amounts of the sulfite and metabisulfite in the fixer, and those are pretty well staple chemicals for other formula(especially sodium sulfite)

The mat works out in favor of mixing it yourself, but let's take the $40 bottle that makes 20L working:

3.7L Ammonium Thiosulfate
2000g Sodium Sulfite
168g Sodium metabisulfite

Artcraft only sells the thiosulfate solution in 1L bottles, so you'd need 4 of them at $9.18 each. That's $36.72 just for this ingredient.

You're also up to needing 5lbs(2,270g) of sodium sulfite, which will cost you $18.11 with enough left over to mix ~2L of D76.

The sodium metabisulfite will still get done with a 1lb bottle, and that's not something I've seen in a ton of formulae in huge amounts, so I wouldn't stress over it. Still, it's something you need to buy and have on hand.

So my analysis just based on this is that it's a wash if you're buying concentrate to make 1 gallon, and the price shifts hugely in favor of commercial if buying larger quantities.

I'll also note that I can't seem to find the smaller bottle of Kodak concentrate without the included hardener, although I know I bought it last year.

For the closest Ilford equivalent, 1L bottle(5L working solution) is $17.87. A 5L bottle is $53.96, which is probably about a financial wash to vs. making it yourself, but diluting a concentrate is certainly easier. I'm a chemist who doesn't mind getting my hands dirty in the lab, but this is somewhere that I'm probably going to be analyzing the next time I'm looking to buy fixer.

In this too, I'm also not looking at fertilizer-grade ammonium thiosulfate, as I can't find a quick online price for it. If I make it to Rural King or the like anytime soon, I'll see how much it is there.

If we're ever able to get Flexicolor III fixer again in moderate-size quantities for home use without buying a full kit, I suspect that will blow any of this math away and make it a no-brainer for those who have in the past used everything.

 

[MattKing]

If we're ever able to get Flexicolor III fixer again in moderate-size quantities for home use without buying a full kit, I suspect that will blow any of this math away and make it a no-brainer for those who have in the past used everything.

Given the sort of volumes Bob might need, this might be a solution for 50 litres of working strength:
https://kodak.photosys.com/collecti...odak-color-negative-fixer-and-replenisher-25l

Again, subject to getting it in Canada.

 

[BobUK]

I see you are in Norway.
A post I read recently someplace was from a person in either Norway or Finland.
They had great difficulties in obtaining raw chemicals to mix up their own developers, fixers etc..
Here in the UK we have difficulties buying quite a few relevant chemicals. Some can be worked around, but a lot are just unobtainable.
Some chemicals are banned from public purchase by the actions of some over zealous environmentalists. Whilst industries can still get away with flushing tons of the same chemicals into the rivers using "Grandfathers Rights."
Terrorist activities have also put the brakes on some chemical sales.
Strong acids are a serious weapons used by all sorts of hot heads.
Sadly the world is moving rapidly away from the good old days when common sense ruled supreme.

In the UK there is great difficulty in obtaining quite a few photographic chemicals, some are not even offered for sale.
They include Glycin, Sodium Metaborate, Borax, Ammonium Thiosulphate, Potassium Dichromate used in the Bromoil Process, strong acids, possibly Boric Acid soon.


Take a look at what you can get in Norway.
Local suppliers and importing may be problematic with your own customs control.
If the situation is as bad as the person claimed in the post I read, you may be in for a difficult journey.

I hope things are not like that person indicated, and you can get hold of the materials required for photography.

Now that you have a list of some of the more common needs, try finding suppliers that will sell small quantities to you.

Good luck, and enjoy.

 

[Carnie Bob]

Bob,
If you can find a Canadian source, this might be another option for you:
https://kodak.photosys.com/collecti...ixer-solution-part-a-to-make-20l-cat-105-9914

View attachment 388389

I found someone who is repping Kodak, problem with Canada Distribution is that the People who should have inventory and distibute do not have stock, Old Mother Hubbard syndrome.

 

[Carnie Bob]

Given the sort of volumes Bob might need, this might be a solution for 50 litres of working strength:
https://kodak.photosys.com/collecti...odak-color-negative-fixer-and-replenisher-25l

View attachment 388460

Again, subject to getting it in Canada.

Hi Matt- Do you feel this could be a good substitute for Rapid Fix or Hypam. there is a new dealer near me willing to support Kodak.

 

[koraks]

@Carnie Bob in general C41 fixer is very suitable as an all-purpose fixer. It's a near-pH neutral, non-hardening rapid fixer. This goes for Kodak, Fuji and other big-brand C41 fixers.

 

[Carnie Bob]

@Carnie Bob in general C41 fixer is very suitable as an all-purpose fixer. It's a near-pH neutral, non-hardening rapid fixer. This goes for Kodak, Fuji and other big-brand C41 fixers.

Ok in the sizes shown Matt I can save at least 40% on Hypam each printing session which turns into good savings.