Dignan NCF-41 Divided Color Negative Developer
In the NOV/DEC 1995 issure of Darkroom and Creative Camera Techniques
Patrick Dignan wrote an article on a divided color negative developer. Everything in this article comes from that source.
Patrick Dignan, sadly now deceased, was a pioneer in the formulation of color chemistry for the home darkroom worker in the United States. As such he had earned the respect of an extensive following of home darkroom workers in compounding their own color chemistry. This article is the result of work that he did...thank him not me.
Of course as a divided developer there is al lteast two baths: Developing agent etc in bath A and the alkali etc in bath B. The reason for having two baths is that when the baths are combined oxidation starts with the predictable effect one must expect on shelf life. This type of developing practice of two...or more..baths has been long practiced in b&w for the same reasons. In the case present it is to provide a divided alternative to C-41 (Flexicolor) developer.
Water (distilled) 300milliliters
Sodium Bisulphite .5 (1/2) gram I added (1/2) to prevent reading as 5 grams.
CD-4 (Kodak developing agent) 5.5 grams
Sodium Sulphite (anhy.) 4.5 grams
Water (distilled) to make 500 milliliters
ph at up to 75ºF: up to 6.5
Time in A bath (including drain time): 3 min.
Water (distilled): 500 milliliters
Potassium Carbonate 53 grams
Potassium Bromide .5 (1/2) gram
Water (distilled) to make 1 liter.
optional: Benzoitriazole (Kodak anti fog #2) 2 milligrams
Ph at 75ºF: 11.8
Time in B bath 6 minutes
As you can see not a difficult formula to put together. There is no need to be able to measure any closer than 1/10th gram
Shelf life has exceeded 1 year. Use an acetic acid stop bath. I, in lieu of anything else, I would recommend 20% vinegar to water
Coventional bleach and fix or blix as otherwise used. 75ºF can be used with extended time.
Since there is some carry over every time film is developed you will eventually find your self with insufficient stock to cover your film. That is when you will need to make more. The amount of time elasped from compounding should not matter. NEVER GET ANY B BATH INTO A BATH OR YOU WILL CAUSE THE A BATH TO START OXIDIZING.
THIS DEVELOPER IS DESIGNED TO WORK WITHOUT A PREWET BATH
Since the time in A bath is used only to absorb developing agent and because the agent will be fully utilized in B bath you can not over develop your color film.
This is designed for tank processing. I do not see a method for use with a JOBO unless you reclaim your ingredients.
Try this as it is aseasy and as economical as you will ever find.
If you are uncomfortable discussing this on line please don't hesitate to PM me.
Well, since I have not used this developer formulation, I have no suggestion as to where to put the HAS, nor do I have any suggestion as to how to change the pH.
As for the formula itself, due to the fact that it is quite different than the actual formula, I can't tell you where to put the missing ingredient and how much to use. The actual formula does not use benzotriazole in any form, and it can harm C41 image formation, while KI is used to moderate the image formation control of the Iodide in the emulsions and the DIR coupler release.
So, as a result, the contrast and color quality will be off as will be the edge effects. IDK which way I can only say that it will vary with each film type you use.
OK - no benzo-triazole. Got that.
You did say something was missing.
What? Do I have to drag it out of you? :-)
I said KI was missing in the post above and HAS, and that BTAZ was not to be used. That is it. I have not used this formula and I have nothing further that would be useful to add.
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
PE - did you exchange on this forum or are there pointers to the discussions? I missed the reference to KI - it was 2am here. Mid morning for you guys. It's all starting to fall into place.
Look in my post #9 above where I refer to KI. I don't have the specific concentration, nor would I hazard a guess because this formula is too alien to me. I wouldn't use it myself.
There are references on APUG to the exact non-split formula with KI.
If you're mainly interested in the developer because it's a home-brew formula, there are others that are likely to work better, such as: one, two, three. I've used both the Dignan formula and #1 in that list, and I get much better results from formula #1. I seem to recall reading something to suggest that #2 and/or #3 are closer to Kodak's "real" C-41, but as I'm satisfied with #1, that's what I'm continuing to use. I like the idea of the long shelf life and room temperature processing of NCF-41, but in my experience it just doesn't work reliably -- some rolls come out looking good, but others are far too thin, often with weird color shifts that are difficult to correct even digitally. If you want to experiment, of course, I won't discourage you, but if you want something that just plain works, I'd steer clear of NCF-41.
Originally Posted by Murray Kelly
Three is more accurate and two cannot be reached.
The link to two I posted earlier works for me. Either it was temporarily down or there's some route-specific problem blocking it for you but not for me.
I can reach it now.
Two and Three are the same formula but vary in using different hydroxyl amine types. No reall difference in result, but rather in keeping.