DIY Mixing Color Chemicals

Bathtub_Rooster

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Hello!

A short intro and then two questions:

I am the darkroom manager at my college in the US and we recently got a huge influx of interest in developing color film. Considering various factors, I am considering mixing up my own color developer (we have a stockpile of blix and stabilizer).

First question, is there a place to purchase small (~50g) quantities of CD-4 and Hydroxylamine Sulfate? Photographer's Formulary does not seem to have the chemicals at all and Artcraft only sells larger amounts. If not, does anyone have any experience or knowledge with a substitute for either chemical?

Second question, I know that C-41 is the widespread process used to develop color film, but is there another process which can be used, aside from caffenol/beeranol/etc?

Any help is extremely appreciated!
 

MattKing

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Welcome to Photrio.
Are you asking about colour negative still film (C-41), colour positive still film (slides/transparency film - E-6), colour movie film (ECN-2 or E-6) or some combination of the three?
Your reference to C-41 implies colour negative still film, but I just wanted to be sure.
 
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Bathtub_Rooster

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Thanks! And color negative film.
 
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Bathtub_Rooster

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I have looked into bulk chemicals like this and Flexicolor. Can I mix these developers with blix from kits such as Cinestill and how long the shelf life is?
A big appeal of mixing my own is the shelf life of individual powder constituents as I would be making batches of ~2 L.

Thanks again!
 

MattKing

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Yes you can mix developers like these with, preferably, bleach and fix from others.
If you must use blix with film, that will work too.
Many here have developed very effective techniques to deal with shelf life concerns.
And even if you only end up getting 3/4 of the potential use from it, it is still much more economical.
 

lantau

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If your college has a chemistry department it might make economic sense. They'll have, or can procure, chemicals you'll need. And the equipment to mix it. In particular to accurately make the dilute iodide solution. Think precision balances, volumetric glassware, etc.

I don't know about US sources of CD4, being in Germany myself. I can buy 50g lots of the various colour developers. However, I ended up not mixing C41 and rather buy it. I wish I could beam over the Hydroxylamine and CD4 to you.
 

mshchem

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Fuji sells a universal fixer for C41 and E6. Dilution is different. Color film chemistry in modest bulk sizes is cheap.
 

mshchem

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On the subject of aging. I have a bottle of Flexicolor C41RA bleach that I opened in 2016. Bleach as an individual solution keeps forever, replenishment rate is something like 7-8 ml/roll. Developer concentrate unopened can sit in a cool spot for 24 months no trouble. Developer and fixer react with oxygen and go bad.
Powders age as well. I have no experience mixing color chemistry from scratch.
 

koraks

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Bathtub_Rooster said:
does anyone have any experience or knowledge with a substitute for either chemical?
Click to expand...
No substitute for CD4.
HAS can be omitted if the developer is used immediately and does not need to be stored. A substitute is theoretically possible but you'd have to shake down a Kodak or Fuji engineer for good info.

Bathtub_Rooster said:
is there another process which can be used, aside from caffenol/beeranol/etc?
Click to expand...
No, not without severely compromising the students' film.

The easiest, most sane and probably cheapest solution is to just buy C41 developer from kodak or Fuji(or Champion or whatever)in somewhat larger volumes (e.g. a few gallons).

If you really must, CD4 is available from China in quantities starting from one kg (2lbs), but you'll pay a price for it in such small volumes. It's sometimes sold on ebay by amateur/small scale confectioners, which is obviously a somewhat random supply.
The HAS is a bit easier to obtain through the standard channels for technical grade chemistry.
You'd still have to face the challenge of making a developer that truly mimics the official product, which is not as easy as the online posts with recipes may suggest.
 

AgX

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Bathtub_Rooster said:
Second question, I know that C-41 is the widespread process used to develop color film, but is there another process which can be used, aside from caffenol/beeranol/etc?
Click to expand...

Your question hints at a seemingly lack of basic knowledge of the chemistry of current colour films. These films consists of an utmost complex systems of layers and chemicals. The basic reaction is that of a chemical called coupler and a chemical called developing agent. Both react to form a dye, a dye forming the image. To form the dye both coupler and developing agent must be made fit to each other, as structural difference have impact on the dye character. Reaction dynamics add to this. This implies that there is hardly a leeway chemically to gain a natural colour image. To gain the expected result there actually is no leeway at all.

What is the reason to make the C-41 colour developer yourself? Concerning costs, the larger commercial kits are cheap seen costs per film. Let alone with the rising costs of colour films in mind.

Concerning longevity of the chemicals: For anyone with chemical knowledge it is easy to store and handle liquids in a way to yield longevity (Autodestruction aside.) Ask your chemical department for assistance.

Your hint at a huge rise in interest and your issue of longevity of chemicals seem a contradiction to me.

You might collect films until you got enough to use up one complete kit of chemicals.

Alternatively you may make a deal with a local lab on a price for processing a certain batch of films from your department in one run.

Overe here the processing market is historically marked by industrial labs, the current price in retail for one roll type 135 in C-41 is about 2€.
 
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RPC

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Bathtub_Rooster,

I mix my own developers from scratch so I do not have to worry about future costs or availability. I have stocked up on the chemicals, which last for years as powders.

Do you have a formula or formulas to try?

If a formula has several grams of sodium sulfite (a preservative) in it, then hydroxylamine sulfate (another preservative) can be omitted and the developer will still last weeks, if not months, if stored properly. That is my experience. The HAS is really only necessary in a formula labs will use in machines that have the developer exposed some degree to air. If you manually develop in small tanks and use the developer once or twice and don't reuse it after that, omitting the HAS works just fine, in my experience.

That said, I can provide you with two formulas, one that has HAS in it and is very close to the official formula, and one without HAS and other ingredients that is much simpler. Both give high quality results when used correctly.
 

Don_ih

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RPC said:
That said, I can provide you with two formulas, one that has HAS in it and is very close to the official formula, and one without HAS and other ingredients that is much simpler. Both give high quality results when used correctly.
Click to expand...

I'd be interested to see those - particularly the second.
 
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Bathtub_Rooster

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Thank you all for your feedback, it is truly appreciated. With the addition of your advice, I will be looking into making buying bulk kits work within my club's budget.

That being said, I am still interested in your two recipes RPC!
 

Romanko

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RPC

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Here are two formulas I have tested with gray scales and a densitometer and give parallel characteristic curves:

distilled water @ 125F-------------800.0 ml
potassium carbonate--------------34 grams
potassium bicarbonate-----------2.3 grams
sodium sulfite------------------------.4 grams (.4, not 4)
sodium metabisulfite--------------3 grams
potassium iodide--------------------2 milligrams
potassium bromide-----------------1.5 g
hydroxylamine sulfate-------------2.4 g
CD-4--------------------------------------4.5 g
distilled water to make -----------1 liter

develop for 3:15 @ 100F

With the above developer I get good results without having to do any pH adjustment. With the formula below, you should adjust the pH to 10.0-10.2 before use, as in my experience it is a little high after mixing.

distilled water @ 125F---------- 800 ml
potassium carbonate-------------35 grams
sodium sulfite------------------------4 grams (four grams)
potassium bromude---------------1.5 grams
CD-4-------------------------------------5 grams
add distilled water to make------1 liter

pH 10.0-10.2
develop for 3:15 at 100F

Be sure you use distilled water and mix chemicals in the order given.
 

koraks

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RPC

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I see no difference in my results comparing it with the Kodak Flexicolor developer. Curves are parallel, indicating correct relative densities. I can, however raise the pH and get more contrast and saturation. So that may be what your Fuji developer is doing. Less of a problem, anyway, if one scans.
 

koraks

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No, the Fuji developer does not give more contrast overall. I know what you mean (and I have done this on purpose several times with DIY developer) and that's not it. Yeah, less of a problem with scanning; it's easy to lift things here and there digitally. It's the attractiveness of digital after all.
 

RPC

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In color there are many variables that can cause problems, but I have not experienced your problem with these developers. As they say, YMMV.
 

koraks

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Yeah, certainly. There are also no guarantees that different film stocks will respond in the same way. My experience was specifically with Fuji Superia 200 IIRC.
 

mshchem

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Mick Fagan said:
To drop the pH, I use acetic acid, 10% solution drop by drop, sufficient stirring to ensure evenness then check the pH.
Click to expand...
Hi Mick, do you use a pH meter or test strips? It's been 30 years since I used a pH meter, there's several inexpensive meters available this day in age.

I remember using (in a chemistry lab) EM Science test strips, expensive to buy the whole kit but these worked well. Of course these strips worked well for checking pH but maybe not so much for adjusting the pH.
Best Regards Mike
 
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