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Can you develop C-41 film with B&W chemistry?

Just spotted your posting here quite by accident, Patrick while browsing. Glad you're back, we need you here. I hope and trust that the OP is still with us as well. 3 pages now and nothing since the first post.

pentaxuser
 
Question:
Is it possible to replace C41 developer with some kind of B&W developer, then bleach and fix and still get usable color negatives? I'm looking for ways to make color developing as inexpensive as possible. Maybe I'll do some of my own experimenting, providing someone doesn't tell me "It's impossible."
 
yes!


refer to patent 4,363,869 column 6 row 5

 
So essentially any B&W developer can be used as the developer for color processes? Why is C-41 developer made of completely different chemicals that don't appear in any B&W developer, then?
 
No! B&W developer develops only a b&w silver image. It won't develop dyes. If you bleach then, you'll get nothing.

BW developing agents are just reductants. Color developing agents are also reductants but after they have oxidized, they have to react with couplers to form dyes. Much more complex reaction.

But well, I've read here that Rodinal can work as a very weak color developer that can form weak dyes with dye-rich films (slide films). Arithil here was doing this kind of work IIRC.
 
Is there anything that can be added to a B&W developer that reacts with the film and forms the dyes? What would adding CD-4 or somesuch to an existing developer do?
 
thisismyname09 said:
Is there anything that can be added to a B&W developer that reacts with the film and forms the dyes? What would adding CD-4 or somesuch to an existing developer do?
Click to expand...

If it worked, wouldn't that be just making a form of color developer anyway?
 
True enough, but its always more fun to make things than to buy them.
 
thisismyname09 said:
Is there anything that can be added to a B&W developer that reacts with the film and forms the dyes? What would adding CD-4 or somesuch to an existing developer do?
Click to expand...

CD4 turns the B&W developer into a pseudo color developer.

In addition, dyes formed from CD4 are less stable.


PE
 
Photo Engineer said:
CD4 turns the B&W developer into a pseudo color developer.

In addition, dyes formed from CD4 are less stable.


PE
Click to expand...

After googling some MSDSs for kodak color developer, I'd assume that the developing agent in kodak's developer is 4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine, correct? That isn't all that different from CD-2, which is, according to the data sheet from the photographer's formulary, 4-N, N-Diethyl-2-methylphenylenediamine. What is it about this, and other chemicals like CD-4, cause dyes to form?

It seems like the similarity between the color developers I've been able to find (and rodinal) is NH2, something that "normal" B&W developers, like hydroquinone and phenidone, lack. By this logic, would amidol (2,4-diaminophenol) have the same (or maybe better?) dye-forming effect as rodinal (4-aminophenol), due to the presence of twice as many amines?

Am I on to something or am I merely thinking that I'm beginning to understand something because I have very basic chemistry knowledge and wikipedia?
 
thisismyname09 said:
Is there anything that can be added to a B&W developer that reacts with the film and forms the dyes? What would adding CD-4 or somesuch to an existing developer do?
Click to expand...

Developing agents - both in BW and color - are the most expensive and "special" components of the developer. So there's no point adding color developing agent to BW developer. Mix a new one, then you won't have BW dev agent there competing with color dev agent, which is a problem. Formulas are available on the Internet. Maybe not the exactly correct ones, but probably better than adding just CD-4 to BW developer.

CD-4 for C-41
CD-3 for E-6 and RA-4
 

HRST has said it correctly as to usage and cost.

Your comments are close here but no cigar! A proper color developer has one NH2 and one NR2 group. This is the combination that forms dyes most properly. Other developers may contain OH and NH2 and form weak transient dyes, but they do not really count in the real world.

Now, to go on, the R groups must be correct for the couplers or the wrong dyes form or the dyes that do form have the wrong stability.

PE
 
i have had students do this by mistake, in fact one last week.

there is image and it is printable, but........... it definately makes life harder (a non scientific answer )
 

Now, at this point, I'm honestly just asking out of curiosity, but:

what would the correct R groups be for c-41 film? I would guess that they'd be the rest of the stuff on the color developer molecule, such as the methyls and ethyls, maybe. What exactly are the couplers made of, and what reaction causes them to form dyes? By dyes having the "wrong stability," do you mean that it will fade with time or that the colors are incorrect?

Better yet, is there a book or website that contains all there is to know about color film and development, so that I don't have to waste your time explaining it to me bit by bit?
 
As posted by HRST, the correct C41 developer is CD4. You have posted the name above so I won't have to repeat it here. The correct RA and E6 color developer is CD3. You might note that one color developer is used for products to be viewed by the human eye and another is used for products to be viewed by other products (printed).

Couplers are very complex organic molecules. I refer you to the article by Rodgers and Kapecki in the Kirk Othmer Encyclopedia. They give details on this. You might also look at a patent by Edens and Vancampen or Bent and Mowrey which show some typical couplers. There are more modern examples, but these come to mind quickly. Basically, couplers have an "active methylene" site which is usually -CH2- or -CHR- or -CH=. The simplest example is para chloro phenol which makes a water soluable cyanish dye.

PE
 
But didn't you just say a few posts back, "dyes formed from CD4 are less stable"? Is that to say that home made developer with CD-4 isn't as good as the kodak brand stuff, or that the whole C41 process is less stable because of the dyes formed by CD-4 as opposed to CD-3?
 
CD4 dyes formed in RA paper form less stable dyes because the dye and coupler combination must be carefully chosen to be optimum for hue and stability. CD3 dyes formed with C41 films will also differ in hue and stability. Stability and hue are a matter of matching a complete coupler set with a single color developer. If they are crossed (as in cross processing) you get the wrong results!

PE
 
Oh, I see.

Thank you, by the way, for taking the time to explain this. Very interesting stuff.
 
"Can you develop C-41 film with B&W chemistry?"

Yes, you can, and it makes it a monochrome negative; a grainy, high-contrast one at that.

If you want a cross process that will give you color results, you can use the E-6 process.

If the question was asked because you took some pix on color negative film because it is all you had handy, but you want the pix to be printed in black and white, I will argue that you will get "better" results on a "standard technical level" by developing the film with its intended C-41 process, and using one of the various methods available to obtain black and white prints from color negatives. There are analog methods, which we can discuss here, and digital methods, which you can discuss on HybridPhoto.org.
 
while digging

found this patent interesting US2226639 Color photography
 
Very old patent with little useful information compared to todays work. Try the patents I suggested above.

PE
 
thisismyname09 said:
So essentially any B&W developer can be used as the developer for colour processes? Why is C-41 developer made of completely different chemicals that don't appear in any B&W developer, then?
Click to expand...

A B&W developer is used as the first developer in a colour REVERSAL process and one could use almost any B&W developer for that step. The colour developer NEEDS to react with the colour couplers, so that is why they generally as based on something like CD-3 or CD-4...

BTW, I have also heard of folks using a CD-4 based developer to process B&W. Should work as long as the film does not contain anything that would react as a colour coupler.
 
Here's some (expired) Kodak Pro 100T 4x5 I processed with D-76:

Graflex 4x5 field camera
105mm f/3.5 lens

It was completely by accident. While in photoschool, I turned in some sheets of Pro100T to be processed (my school runs its own C-41 and E-6), the lab manager said he didn't recognize the notch-code, and told me it was probably T-Max 400 (my school didn't have enough funding to pay for extra color chemistry, so our instructors/lab techs were overly cautious). And I had shot some TMY previously, so I took him on his word, just figured I must've loaded the wrong film.

I processed it in D-76 (stock) as if it was 4x5 TMY (20ºC - 6.75min). When the negs were finished drying I could tell something wasn't right.. They were WAY too dense and just had a weird look to them. I found a reference for the Pro100T notch code, and sure enough, the lab manager was wrong.

The only other problem was a strange red stain on one of the photos (I never figured out what caused that). I never printed them, but I scanned them on a Epson V700. And I recall them scanning very well, but the tonal quality was a good bit muddy..
 
I just developed an expired roll of Kodak 400CN 120 film. My plan was to use Rodinal 1:100 stand development for one hour. So I poured in the developer, took off to a local shop, and got stuck in traffic (the King of Saudi Arabia's motorcade closed the road), and got back after two hours had elapsed. The film was certainly developed (!), came out with a pronounced dark red/brown stain/fog on the entire roll. BUT -- when scanned and adjusted in levels, the images were quite usable and very grain-free.
 
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