Developer Formulas for C-41 film?

[sanking]

If you have heard of PyrocatHD you know that I am not a novice in formulating film developers for B&W film. But I know nothing of the requirement of developer formulas for C-41 type color films. I can see that there are a number of do-it-yourself developer formulas available in kits for C-41, but I would like to understand the chemistry better in order to mix my own. Any guidelines or references to information on this subject would be appreciated.

Thanks in advance for any information on this subject.

Sandy

[Kiwi7475]

Sandy,

Here’s some pointers:

https://www.photrio.com/forum/thread...rmulas.142062/

https://www.photrio.com/forum/thread...emistry.61242/

Not totally satisfactory, but it’s a start.

[LabRat]

Camera & Darkroom magazine had some refined formulas long ago, so look for those... (I have these on-file somewhere, but not accessible now...)

Pretty simple, just have to find CD-4 (Artcraft)...

Good luck!!!

Steve K

[koraks]

I've done quite a bit of DIY C41 and the differences between the various formulas I tried (including the ones linked to earlier) were minimal. I also found it just wasn't worth the hassle; the quality of the negatives was still not quite up to the level I get with Fuji chemistry, which also is very cheap, easy to use and lasts long. For B&W I still roll my own, but for C41 it's just not worth it for me, currently.
I do keep a small stash of cd4 at hand...for emergencies or something. I sold off most of my stock though.

The morale of all this: be clear at least to yourself why you want to do this and what you want to get out of it. Other than that, go ahead and do it; it's not too difficult to run some tests with small variations in chemistry.

[Mick Fagan]

I did C41 using about three different C41 formulae, one was from a local industrial doctoral chemist, which worked the best. The other two were ones that I had picked up here and there. This was in the mid to late eighties and within reason, one got very good to excellent colour negatives for wet printing. However if one developed a Kodak control strip and had it read at my work (Industrial colour lab) the parameters weren't quite there.

Fast forward to November/December 1988 and Bertram W. Miller had an interesting article called "Managing Your Color Photochemistry" subtitled, "Keep a Balance In Your Darkroom."

This appeared in the Nov/Dec 1988 edition of Darkroom & Creative Camera Techniques, pages 23 to 25. this article did give some insight into C41 chemistry and no matter how much he tried, he just couldn't emulate Kodak C41 chemistry. To that end, he started using Part A of Kodak's C41 developer with bulk chemicals, ending up with excellent results.

I tried his technique and after running Kodak C41 control strips and having them read at my work, the results were so good, a visiting Kodak chemist who had got wind of what I was achieving in a home darkroom, one day asked how I was doing this.

I'm not suggesting you copy Bertram's method, but his article is very interesting.

[Ironage]

Here is a good reference I use: https://www.bonavolta.ch/hobby/en/ph..._chemicals.htm. I have been experimenting with these for about a year. I use the divided bleach and fix formula for both film and paper. So far so good, but you cannot store this developer and get good results. I mix up a fresh batch right before use.

[sanking]

Thanks to all who replied with useful information.

I have quite a bit of old color film, some of it frozen and most likely good, but some stored without freezing but in favorable conditions. Color balance is not vintage to my interests as my plan would be to scan the film and then color correct in PS so would be able to correct for this. What is important is a simple formula, with as few solutions as possible, and that I could use in range of temperatures.

In looking at some of the available commercial formulas I see that one or two have only two solutions and appear to be useful in a range of temperatures and they might serve my needs so I will probably try one of these before attempting to mix my own.

Thanks again, and any additional comments would be appreciated.

Sandy

[rob4x5]

Sanking, if you decide to mix your own, here is a simple developer formula to try:

distilled water @ 125F 800 ml
potassium carbonate 35 g
sodium sulfite 4 g
potassium bromide 1.5 g
CD-4 5g
add distilled water to make 1 liter

I found it gives parallel characteristic curves, but it must be used at 100F and pH adjusted to 10.0 to 10.2 to achieve these results, similar to commercial developers. It has no usual hydroxylamine sulfate for the preservative, so shelf life will be shorter than usual but I have found there is enough sulfite in it to last many weeks.

If you use any developer at temperatures other than 100F, you can expect to get some degree of crossover (non-parallel characteristic curves), so whatever you use, run some tests to see if the results are acceptable to you before using on anything important. Based on your stated color needs, I think my developer would be completely adequate.

[sanking]

Sanking, if you decide to mix your own, here is a simple developer formula to try:

distilled water @ 125F 800 ml
potassium carbonate 35 g
sodium sulfite 4 g
potassium bromide 1.5 g
CD-4 5g
add distilled water to make 1 liter

I found it gives parallel characteristic curves, but it must be used at 100F and pH adjusted to 10.0 to 10.2 to achieve these results, similar to commercial developers. It has no usual hydroxylamine sulfate for the preservative, so shelf life will be shorter than usual but I have found there is enough sulfite in it to last many weeks.

If you use any developer at temperatures other than 100F, you can expect to get some degree of crossover (non-parallel characteristic curves), so whatever you use, run some tests to see if the results are acceptable to you before using on anything important. Based on your stated color needs, I think my developer would be completely adequate.

Hi Rob,

Well, that is certainly a simple formula that should be easy to mix. I am definitely able to maintain temperature of 100F and adjust pH to 10.0 to 10.2.

But what is CD-4?

Sandy

[Kiwi7475]

Hi Rob,

Well, that is certainly a simple formula that should be easy to mix. I am definitely able to maintain temperature of 100F and adjust pH to 10.0 to 10.2.

But what is CD-4?

Sandy

That’s 4-(N-Ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine sulfate

https://en.m.wikipedia.org/wiki/Colo...loping_Agent_4

available here: https://www.artcraftchemicals.com/pr...d-4-part-1095/

Also overseas:

https://www.macodirect.de/en/chemist...-c-100ml?c=649

https://www.ebay.com/itm/COLOR-DEVEL...gAAOSwdjNZEcvX