Kodak AE-31, C-41/E-6 pre-dev with bw chemical

[Rafael Ramos]

Greetings.
I humbly come before ye in search for enlightning: This forum has being the recurrent result of all my last inquiries to the oracle and repository of deep knowledge so i lay here my doubts.

My wish is to shoot colour slide high-ei (3200+) and achieve a t-maxP3200ish look but with colour for project/magnify viewing: very high contrast, deep blacks, almost blown highlights and at least a resemblance of the scene colour.

i've been using c-41 film processed in bw only for a while (it is cheaper and easier to find down here in brasil) and managed to get some impressive results pushing ultramax 400 with id11. i was searching for a way to get hid of the undeveloped pigment and happened to stumble uppon Kodak AE-31 Technical Data.

let me quote the part that got my attention:
"If you want color prints or color slides from your films (except KODACHROME Films), you can bleach and process the negatives to obtain color negatives. In many cases, this procedure will restore reasonable color images to the negatives so that color prints or slides can be made from them." (yadayada, unreliable, unsure... i got that part too...)

I got the 'recolouring' the C-41 quite well: you have the silver and undev pigment still there. Just "cd-4" them together and you have a shiny colour negative after the proper bleaching and all the rest.

what i couldn't wrap me dumb head around was the slide part of it: as far as i understood for e-6 you need the halides, not the silver, to activate the pigments and the bw dev would have washed it out.

at last i reach my point:
i want to pre-dev my e-6 in bw (testing which bw trickery would yield the best result) and send to the lab to finish the color dev. They would, then, bypass the first bath in the process.

what should i do in hope to maximize the chances of success?
a) full dev/fix as bw-neg, ask for e-6
b) full dev/fix as bw-reversal, ask for e-6
c) bw dev but not fix then fog (and also chemicaly fog during e-6 'for good measure')
d) bw dev, not fix, fog, ask for c-41 bypassing the first bath (like those guys making E-6[-] with c-41 chem)
e) give up, sledghammer the cameras, drink the chems, curl in a bunch and cry.
f) none of the above. but i have an idea...

 

[koraks]

i want to pre-dev my e-6 in bw (testing which bw trickery would yield the best result) and send to the lab to finish the color dev. They would, then, bypass the first bath in the process.

Have you checked with any labs if they are capable and willing to do so? Keep in mind that most labs, at least for roll film formats, use automated processors (dip & dunk or roller transport) that technically cannot be manipulated to skip any processing step.

Some other comments:

• C-41 on E-6 film is cross-processing and the resulting dyes will not be of the intended color and long-term stability. I'm not sure how important these things are to you, but if they are, you can rule out any process in which you run E6 film through C41 chemistry.
• I'm not sure what the impact on image quality will be if you develop & fix your E6 film at home and then dry it and ship it to a processing facility with the inherent time delay involved.
• If you want a very high-contrast look, simply develop the heck out of your E6 film in the first developer step. Then process normally for the rest of the process. It'll be a challenge to keep fog down in that first developer step though, particularly with the kind of expansion you intend to do ('push' to 3200, which would be at least a 3-stop push if you use 400 film and even more for slower film).

as far as i understood for e-6 you need the halides, not the silver, to activate the pigments and the bw dev would have washed it out.

In both E6 and C41 the basic principle is the same: the color dyes (not pigments) are formed as a result of oxidized developer binding to the embedded dye parts in the emulsion. Hence, the colors are in essence a byproduct of developing the silver image. The silver image is in regular processing consecutively bleached and fixed away, leaving only the dyes. So if you mean this by 'needing the halides', then yes. You need exposed silver halides and a color developer whose oxidated remnants bind with the dyes in the film. This is true for all contemporary color materials: C41, E6 and RA4.

I think your best/most practical bet to make this work would be one of two options:
1. Contact a lab and ask them how much they can push E6 film in their process. Generally, I think a 2-stop process is the maximum in most automated processing equipment, but who knows.
2. Run the entire E6 process yourself and modify the first developer step to suit your purpose. You can start by raising first developer temperature and/or processing time, but with the kind of push you're intending, you may have to modify or entirely reengineer the first developer chemistry as well.
Option 2 would evidently give you the most flexibility particularly in the testing stage (no waiting for the lab to get your test strips back). Option 1 would be the easiest, but with the inherent limitations of what your lab is able/willing to do for you.

 

[Rafael Ramos]

thanks for the answer, Koraks

about the processing lab: i have an e-6 in town and i could get the film there still wet.

they are fond of art and even experimentation. they would dial zero time in the machine first step (efectively bypassing the dev), or some specific time if i ask but i think it wouldnt do for the purposes i seek. if it were the case someone would already have done it successfully.

i am thinking more of crazy stuff like "1h30, 1:25 id-11, constant agitation" or "1:200 standing for 3 days in the fridge" or other "artistic" attempts could somehow can achieve the look i wish. (just to make you easy: these are just 'absurd for fun options', i dont think i'll try any of these. yet.)

So if you mean this by 'needing the halides', then yes.

let me try to explain better my doubt:
in c-41 the pigment develops in the presence of developed metalic silver and not the silver halide, right? (the undeveloped halides play no role in then pigment formation and are washed away in bleach)
so, if i was trying to do this with c-41, i would just follow the kodak ae-31 info and fully dev&fix the film for a bw standardish negative (wouldnt even need to bleach) and handle to the lads at the lab: they put it in the machine, it tries to develop it for no avail (the halides are already washed at home) and keep the rest of the process. presto: negatives ready for printing.

my doubt is how e6 develops the pigment:
1) does it need (fogged) undeveloped halide?
2) if i wash the undev halide off during bw fix the remaining developed metalic silver will develop the pigment? (ae31 leads me to believe this is true)

if #2 is true then:
1) should the bw processing be negative?
2) should the bw be reversal?
(in any case if fixing/washing the bw doesnt mess the pigment formation my whole drama ends: i develop bw 'as i wish' and the guys at the lab just process it at box rate. won't matter what the machine tries in the first bath.)

i am keeping this point because of kodak ae31: somehow this is doable. the question is 'how?'

 

[koraks]

fully dev&fix the film for a bw standardish negative (wouldnt even need to bleach) and handle to the lads at the lab: they put it in the machine, it tries to develop it for no avail (the halides are already washed at home) and keep the rest of the process. presto: negatives ready for printing.

No, it doesn't work that way. The dyes (not pigments) are formed during development of silver halides into metallic developer by a color developer of the ppd family. The dyes are formed through combination of molecules in the emulsion and oxidation products of the color developer, which emerge as the result of the color developer developing silver halides into silver metal.

E6 forms dyes in a similar way as c41. The first developer creates a negative silver image. This is bleached back. Then the unaffected silver halides are developed in a similar fashion as in c41 processing, and ultimately all developed silver and silver halides are bleached arrend fixed out, leaving just the positive dye image.

In your idea, you would just replace the lab's first developer step with your own, leaving all other steps to the lab in standard E6 fashion. So your own fir at developer step will indeed create a negative silver image. The resulting positive dye image is created on the basis of the silver halides that are unaffected by your own custom first developer.

 

[Rafael Ramos]

(sound of gears working...)

so as the 'hidroquinone' sets the Ag free from the halide the remaining (Br, I, whatever) reacts with the dye loci (is it the proper nomenclature for the dye precursor?) and forms a latent dye nucleus which is further developed by the CD-4 later in the process?

regarding AE-31 statement: since the dye seed and the rest of the untouched dye are not washed away during bw fix the CD-4 of reprocessing it is able to further develop it back into colours.

but i still don't grasp how would the slide (except kodachrome) would be colourizable after complete bw as kodak states.

if you want to check the thing to see if i am missing something...
https://125px.com/docs/techpubs/kodak/ae31.pdf

 

[koraks]

(sound of gears working...)

[/quote]so as the 'hidroquinone' sets the Ag free from the halide the remaining (Br, I, whatever) reacts with the dye loci (is it the proper nomenclature for the dye precursor?) and forms a latent dye nucleus which is further developed by the CD-4 later in the process?[/quote]
Well, no hydroquinone is involved, really. Maybe in your B&W developer, but not in a color developer. Color developers (CDx) are all PPD-derivatives (para-phenylenediamine) to the best of my knowledge. This is relevant, as opposed to hydroquinone, these PPD-derivatives, as a result of their developing action, release smaller molecules that bind with the color couplers in the emulsion and thus create the color dyes that you can see. The couplers themselves are colorless, but combined with oxidized developer molecules, they create the visible dyes. So basically, this is what happens (at least the quick & dirty version to my understanding):
Silver halide + color developer (e.g. CD3 or CD4) --> metallic silver + oxidized developer molecules + halides (mostly Cl- and some I-)
Oxidized developer molecules + dye couplers --> color dyes

On a sidenote: notice that the halides do not directly play a role in dye formation. They are relevant, as they do interfere with the dye formation process just like they do in B&W development (where Br- is used as a restrainer, remember?) The halides are important in creating correct color balance (selective inhibition of development in different color layers), they influence grain/dye cloud formation (thus influencing the 'graininess' of the image) and they influence acutance of the image. However, again, the halides do not themselves trigger dye formation or end up in the resulting dyes. You could say they are an (important) byproduct of development - and of course the halides are essential in making a developable emulsion.

regarding AE-31 statement: since the dye seed and the rest of the untouched dye are not washed away during bw fix the CD-4 of reprocessing it is able to further develop it back into colours.

Yes, essentially. The 'dye seed' as you call it are the dye couplers: colourless molecules that when combined with oxidized developer turn into the cyan, yellow and magenta dyes that make up the image. With B&W processing, these dye couplers remain embedded in the emulsion. So if you were to add oxidized color developer to the emulsion, the oxidized developer will combine with the couplers and create dyes, regardless if a silver image is present or not. One way of doing this is bleaching back an existing silver image and redevelop it using a color developer. This is what the AE-31 tech pub outlines: take a black-and-white processed color negative film, bleach back the silver image with a rehalogenating bleach so that the metallic silver is turned back into silver halides, then redevelop using C41 chemistry. In the C41 process, first the silver image is redeveloped creating oxidized CD4 as a byproduct which combines with the still present dye couplers to form the color image. Then the silver image is bleached and fixed in the further processing steps.

Another sidenote: the presence of the color dyes in an already developed color film can also cause problems. A notable instance is when an inappropriate bleach is used (instead of the PDTA/EDTA bleach as used in current color chemistry): e.g. when a ferricyanide bleach is used righjt after color development with color developer still remaining in the emulsion (no intermediate wash step), the ferricyanide bleach will instantly oxidize any remaining CD3/CD4 and this will create an overall/non-selective dye image: fog.

but i still don't grasp how would the slide (except kodachrome) would be colourizable after complete bw as kodak states.

Color positive film is in essence not all that different from color negative film: it has silver halides, color sensitizing dyes and dye couplers just like a color negative film. But in color positive film, it is not the initially in-camera exposed silver halide that is used to create the dye image (through color development), but the silver halide that remains after the negative silver image has been developed and bleached. This is also why in E6 processing, the first developer is in fact not a color developer, but a (specifically formulated) B&W developer - we don't want to create a color dye image yet in the first developer as that would be a color negative image which we don't need (or want)! The color image is created in the subsequent color development step which acts on the remaining silver halides that were not involved in the first development.

So it follows that if you were to take a fully B&W-processed slide film (i.e. developed AND fixed), you could only make a color negative image out of it. After all, the B&W processing leaves only a negative silver image and only in places where that silver image is present, we can activate the color couplers by bleaching and color developing the silver image. The positive image (as it were) has been fixed out by the B&W fixer, so we have no access to that anymore. This is different in your scenario where you specifically want to proceed with positive development. This means that in your case, you only want to run a B&W development step and no fixing before you do any color development. You then bleach back the silver image using a non-rehalogenating bleach (you don't want the silver image to turn back into silver halide, as that would then be involved in further development and obliterate the image), fog the remaining silver halide (with light or chemically; it is done chemically in commercial E6 processing), then color develop it with a CD-3 based developer, followed by bleaching and fixing of the positive silver image which we don't need in the end product.

if you want to check the thing to see if i am missing something...
https://125px.com/docs/techpubs/kodak/ae31.pdf

The aspect you seem to have skipped earlier by the looks of it is the bleach step of the silver image. That one is essential in making a color image from a B&W-processed color film. However, the tech pub does not necessarily bear any relevance on your E-6 experiments. For your purposes, it makes more sense to look at detailed descriptions of E-6 processes, the various steps in the E-6 process, what purpose they serve and what kind of chemistry is generally used for them. There's been quite some discussion on DIY variants of E-6 in the past, in particular the first developer step, so you may want to do some searching on that. You'll find that a lot has been tried and there are some formulas out there that (kind of) work in a DIY setting.

 

[Rafael Ramos]

Thanks for your huge patience in writing such a wonderfull lesson, Koraks.


the reversal bath in e-6 is a non-rehalogenating bleach (and fogging), right?

so the easy way to do that would be "c)" on my first post: bw dev, not fix, skip dev in e-6 lab straight to reversal/fogging if they can do that.

about doing the whole e-6 thing at home: i am not afraid of the process. the hard part for me is getting a hold of the chemistry and putting use for the gallons i'll have before it decays (and throw quite a lot of money down the drain) . that is why i rather have only the first dev and leave the rest for the lab.

also i isolate only one step to tweak: 1st dev. the rest i know will be excatly the same every attempt. this would speed up the trial and error process.

 

[Rafael Ramos]

OR

i could make a full bw reversal to the fogging and do not redevelop, then after proper washing throw straight into the e-6 colour development for the rest.

 

[koraks]

Thanks for your huge patience in writing such a wonderfull lesson, Koraks.

You're welcome. Keep an eye out for some people more knowledgeable than me to come by and set the record straight on anything I may have gotten wrong.

the reversal bath in e-6 is a non-rehalogenating bleach (and fogging), right?

Depends on what you mean by 'reversal bath' - as you imply, reversal is not really a single bath. The E6 process is roughly as follows:
1. First developer; mainly determines contrast and white & black points
2. Non-rehalogenating bleach; removes the negative silver image, leaving the 'positive' image as silver halide.
3. Fogging step; activates all unprocessed silver halide to make it developable. Either done chemically (e.g. stannous chloride) or with light.
4. Color development; creates a positive silver image and a positive color dye image.
5. Bleach; turns the positive silver image back into silver halide.
6. Fix; removes the silver halides from the positive silver image, leaving just the color dye image.
7. Conditioner to improve stability of the dye image
8. Wash

so the easy way to do that would be "c)" on my first post: bw dev, not fix, skip dev in e-6 lab straight to reversal/fogging if they can do that.

Yes; if your lab can totally skip step 1 (first developer), that could work.

about doing the whole e-6 thing at home: i am not afraid of the process. the hard part for me is getting a hold of the chemistry and putting use for the gallons i'll have before it decays (and throw quite a lot of money down the drain) . that is why i rather have only the first dev and leave the rest for the lab.

The developers, and particularly the color developer, and potentially the chemical fogging bath can/will go bad on you after a few weeks, so that may be a factor in planning your process. You may or may not get satisfactory results with partly home-brew chemistry, especially the three components I mentioned. Personally I'd use a ready-made bleach and fix as those are uneconomical to DIY in any case. The first developer is always a bit finicky due to the necessity of a developing agent that is very hard to come by.[/quote]