Alternative E-6

[mts]

A lot has been posted in the past, in published articles, and in various web pages about scratch-mixing E-6 chemistry. It's more difficult to achieve a proper speed/contrast/color balance with reversal films than color negative, but it can indeed be done with care and patience to test your chemistry.

Scratch-mix E-6 appeals to me for a couple of reasons. First, I started photography about 50 years ago mixing chemistry from the Kodak B&W formulae, as I was taught to do by a seasoned photographer who began his work in the 20s (that's the nineteen-20s). It was only much later in the 1960s that I learned you can actually buy chemistry kits.

Second, I process very little reversal film and want to have small quantities (1-liter) of chemistry readily available when I have a few rolls to process.

Third, an aspect that is interesting with reversal chemistry is the ability to modify the contrast and also (to a lesser degree) the color balance by adjusting the chemistry. Of course hand-processing E-6 makes push or pull processing easy, although that is of less interest to me now. I used to do some astrophotography with E-6 films and push-processing with contrast adjustments was important in days before CCD detectors completely eliminated photographic emulsions from astronomy.

The examples here are 35-mm Fuji Provia 100 processed in E-6 scratch mixed chemistry by hand in Nikkor tanks and reels. The scans were made from the positives with a Nikon 9000 ED.

I didn't have a recent MacBeth chart strip handy, so I processed one from film that was exposed several years ago and has been stored in the freezer. The scenic shot was made and processed last month (Feb. 2009). These films were processed using light reversal and with quinone bleach instead of the usual Fe-EDTA formula.

If anybody has interest in pursuing E-6 alternatives I will be happy to e-mail the formulae that I used.

 

[Photo Engineer]

Your neutral, on my screen, goes from white to bluish to brown. If so, that is ungood.

PE

 

[epatsellis]

MTS, a more informative test would be a control stip, with attendent densitometer readings. Then (and only then) could you declare the process a success.

 

[analogsnob]

I mixed E-6 from raws for many years with success but process control was a religion with me. Small quantities can be tough to mix consistently. I also found that any deviation from the Kodak formula invariably caused something ungood to happen somewhere. By that I mean a great many films process in E-6 but not all respond in the same way especially when pushing and pulling. Some may be fine, some may be ok normal, some will suffer from a host of cross overs and other ugly things.

I guess I'm saying it can be done but when it counts be sure you know where the monsters dwell.

 

[geoferrell]

I've thought about processing E-6 but don't have equipment, but would try stainless steel tanks and reels if I thought I could get the right results. With E-6 does temperature control have to be right on the money for the chemicals and rinse, or can slight variations occur and still get reasonable results?

 

[mts]

I certainly agree that process control is more difficult with E-6 especially so when mixing in 1-liter quantity. You have to mix component solutions carefully and pay attention to measurements and pH of the final solutions. Please don't think that I make any claim for duplicating Kodak's chemistry--not by any means.

The greenish shadow on the grey card is evidently a shadow cast by the tree that is nearby the place I set my chart for the picture. The same shadow appears in a C-41 sample that I posted in a different thread, so it is definitely not a processing artifact. I suppose it's time to take more test images and that more care should be used in their creation. I have no densitometer and no facility for producing calibrated test strips so my measure has been good images that scan well. I avoided using positive film for quite a long time because so many monsters hide in the exposure and processing, even when using commercial processors. Some of my worst results came back in the mail. E-6 film does not like its latent image to be stored or mis-handled--nor does unexposed reversal film for that matter--which makes finding commercial processing increasingly difficult for people who live in the wilderness.

I use Nikkor tanks and reels held in the water bath for temperature control. It's fairly easy to hold within a degree for the ~7 min. that is needed. Temperature control is most important for the first developer and the color developer. The other solutions process to completion and their temperature range can be relaxed in my experience. I rinse using warm water and hold the reels a few inches from an outdoor flood lamp mounted above the sink for reversal exposure. Processing E-6 by hand in small tanks does test your darkroom technique. Good wet-side technique comes with practice.

 

[stefan4u]

Dear mts !

I’ve tried a similar thing 1 ½ years ago for processing a batch of somehow pre-aged / wrong stored films. This was quite a hassle, but very instructive in a way.
At the end I was at least able to process these “somehow off” films better than with commercial chemistry.

Link: (there was a url link here which no longer exists)

I would be very interested in your formulation; most published formulations are not working very well…

Regards from Germany,
Stefan

 

[mts]

Your link appears to omit the ethylenediamine component in the color developer. It's a necessary component that can be found (with difficulty) in solid form as the sulfate, or in liquid as the free-base which is what I use. Unfortunately the free-base is one of the nasty chemicals one does not like to handle!

 

[Photo Engineer]

Also not used in most formulas is Hydroquinone Monosulfonate. This is used to balance development rate between the 3 imaging layers due to the thickness of the film. HQ by itself is too active and will tend to overdevelop the top layer while underdeveloping the bottom layer. The HQMS diffuses faster being more ionic even if larger, but it develops more evenly and slowly.

This is detectable often if you look at grain and sharpness, even if you compensate somehow for the color imbalance it may cause.

I keep telling people that HQMS was used for a reason! HQ is not what you should use in the first developer!

PE

 

[stefan4u]

Dear mts, dear PE!

Yes I know the mentioned stuff is not perfect, but remember I did it to process films that where somehow off and not acceptable in commercial developers.

That formulation lacks a contemporary chelating agent (like dequest 2000, was surrogated by calgon) and a different silver solvent agent (Ethylenedithiodiethanol or another thiol was surrogated by Sodium thiocyanate).

But what is is (was) Ethylenediamine (EDA) used for?
As reactive as it looks, it seems not to be a chelating agent like EDTA, more a kind of silver solvent / bleach. Looking to older E-4 formulas intensify these thoughts.
Is that right?

If it is as nasty as described, was it replaced by XY-thioles for environmental reasons as well as the butylamine borane?

Regards,
Stefan

 

[Photo Engineer]

Stefan;

In E4, TBAB (t-Butyl Amine Borane) was used as a fogging prebath before the color developer. In E6 it was replaced with the less toxic Stannous Chloride. Both of these solutions go bad rather quickly so take care.

The DTOD (Di-Thio-Octane Diol or Ethylenedithiodiethanol) was used in B&W motion picture reversal processing, but not AFAIK, in the E6 process. It may have been later introduced. The EthyleneDiamine used in E1, E2, E3, E4 and E6 is there as a silver halide solvent to help grain structure and promote dye formation.

Some of this is discussed in the book by Eaton on photographic chemistry, and an E1 or E2 formula is given there.

The HQMS was first used in E6 to offset the high activity of HQ at 100F when processing thick films.

PE

 

[stefan4u]

Dear mts, dear PE!

There is still a question about the Ethylenediamine…

OK, it can be substituted by Ethylendiamine sufate, in an amount of about 8 g/litre due its larger molecular weight, but stays a more exotic stuff which is not merchantable for me without a hassle.

If it’s more than a silver solvent and is able to help dye formation (probably more in the deeper regions of the emulsion) or enhance the contrast, wouldn’t it be possible to reduce one of the CD-3’s antagonist (CZA for example) if no Ethylenediamine is available, to compensate this lack and keep contrasts and densities in line?

Just asking, because this seems the way Kodak managed this in the former "E-6 hobby kit / single use kit".

There is no Ethyldiamine / Ethyldiaminesulfate involved but Ethylenedithiodiethanol (Tegochrome 22) and a distinct reduced amount of CZA to about 0.56g/Litre, which is usually stated around 1.3 till 1.5 g/litre. With my limited knowledge and access to literature I couldn’t find other properties for Ethylenedithiodiethanol exept as a silver halide solvent. This trick could reduce the chemical costs considerably, no EDA, less CZA needed.

Ethylenedithiodiethanol “sleeps” in my cellar, this would fit nicely…

Sources (of my suspicion)

http://www.freepatentsonline.com/5198517.html
scroll down till the E-6 formulation begins,

http://www.freepatentsonline.com/5948604.html
keep a calculator nearby, divide given amounts for CD part A by 5.

Regards,
Stefan

 

[Photo Engineer]

Lower CZA increases Dmax and contrast and changes the interimage effects. IDK offhand what changing it would mean. You are discussing making a lot of changes.

As for using Tegochrome 22, it is extremely expensive compared to Ethylene Diamine.

PE

 

[mts]

My understanding of CZA is that it mitigates formation of colorless dye components and therefore effectively lowers or raises color contrast (saturation). I don't believe it is at all interchangeable with eithylenediamine which I understand, as PE stated, contributes to dye formation in the deeper layers.

You can experiment with the color chemistry by processing test film through the reversal and bleach. Wash after the bleach and then dry the film for later re-wetting. Cut the test film into strips for later processing with various formulations of color developer followed by the usual fix and wash. That way you can evaluate the effects for film samples that were all processed with the same first developer, reversed and bleached the same, and of course that were all exposed the same. In this way you can test Tegochrome 22 if you have it available, and can compare with a test that is processed in the standard E-6 color developer chemistry. If you get some results, please post them for all to see.

 

[stefan4u]

Dear PE dear mts!

Well I know that lowering CZA will increase the contrast due less competition to oxidised color developer.

What I just want to know is weather less EDA impact can be compensated by using less CZA. There must be a reason for the dosages I’ve found in these two links above. Or asked the other way, does EDA increase contrast, next to solve silver halides ??

Tegochrome 22 / 2,2-Ethylenedithiodiethanol may be more expensive by itself, but paying freight from (for example) Canada to Germany or being “forced” to buy a whole Kg does not make EDA more attractive...
Simply looking for alternatives which make (some) sense

Regards,
Stefan

 

[Photo Engineer]

CZA and Ethylene Diamine are not related in any way AFAIK. So, no, they cannot be interchanged.

Lower CZA for example, can lead to higher cross contamination of color in the active E6 color developer.

DTOD and SCN are interchangable to some extent, but IDK if you can fully interchange them. I do know that you should not mix them except at extremely low concentration and I cannot remember the proper ratios of that mix.

PE

 

[stefan4u]

Thank you both anyway!

I think I caused a misunderstanding somewhere; this is simply not my native language…

It was not intended to interchange CZA and EDA, just want to work out the effects of EDA.

What I would like to interchange is EDA against Tegochrome22/DTOD (if possible), simply because latter is present. In this context it’s interesting that DTOD is (partly) interchangeable to SCN, the stuff I’ve always took

Regards,
Stefan

 

[Photo Engineer]

AFAIK, EDA and DTOD are different in their effects as well.

DTOD is a straight silver halide solvent and must be used at low level and concentration. EDA is more like a cross between DTOD and Benzyl Alcohol from my understanding, in that it promotes development but at the same time, promotes coupling.

PE

 

[stefan4u]

Dear PE !

Thanks’ for clearing that, this way it makes sense, even for my mind.

(but it will be hard, not to fall in love with benzyl alcohol again)

Regards,
Stefan

 

[Photo Engineer]

If I were to experiment with anything, I would use Benzyl Amine. GAF used that in their reversal formulas to perform 2 or 3 functions. Beware though. It stinks! Kind of like some biological functions going bad.

PE

 

[stefan4u]

Dear PE!

I’ve read somewhere your comments to the former anscocrome developer, their need to avoid benzyl alcohol by (patent) law and that smelly “drop in“ replacement.

By the way, is there a realistic chance to increase saturation with benzyl alcohol or benzyl amine in E-6 emulsions, or increases stain only?
I’m aware of benzyl alcohol’s absence in contemporary formulations, so this question is maybe answered already by itself…

Any ideas ?

Regards,
Stefan

 

[Photo Engineer]

Stefan;

BZA smears images decreasing sharpness. It was eliminated from E6 for this reason. IDK what it would do to E6.

PE

 

[stefan4u]

Dear mts, dear PE and of course hello to all other.

First a big excuse for “hijacking” mts’s thread so badly, sometimes I’m just too curious. Sorry, sorry, sorry

I’ve found a German supplier for EDA, we’ll see if it comes through. The week after the next I do have some holidays (if the number of staff stay away sick will not increase anymore…) , then I will do some experiments with / without EDA.

Thanks’ for all inspiration again

Regards,
Stefan

 

[stefan4u]

EDA andt BTZ influence

Dear mts, dear PE (and Hello to all other… )

Times goes by, this should have done much earlier…
According your hints I’ve tried Ethylene Diamine in the Color developer and Benzotriazole in the First developer in a “cross check”.
I’m still using my somehow preaged / fogged / bad stored Agfa precisa 100 Slide Films in the same way with my former formulation.

4 Attempts:
1: FD (my) standard, CD (my) standard with SCN
2: FD (my) standard, CD + 2ml/L Ethylene Diamine (EDA) added, no SCN used
3: FD + 0.1g/L Benzotriazole (BZT), CD (my)standard with SCN
4: FD + 0.1g/L BZT, CD + 2ml/L Ethylene Diamine, no SCN used

Adding Ethylene Diamine does increase density about 0.2 Densitometry units without changing color balance, this seems to be indeed a very useful stuff!
Surprisingly additional BZT in the FD does have a much bigger impact, around 0.3 units in density, but does harm the color balance visible. I assume that the inhibiting of developing process is more prone to the top / upper layers, so a magenta cast will be visible after complete processing.This would fit to the usage of plain hydroquinone (instead the sulfonated) in some formulations.

I will try this again with lowered BZT (0.02 till 0.05g/L) in combination with Ethylene Diamine in the Color developer. Latter may need a ph regulation again.
This is still in (terrifying slow) process, don’t expect me back that soon

By the way, BZT seems to be only useful for preaged / fogged Film, but have to be used with care. Fresh material does not need this “trick”

Regards,
Stefan

 

[Athiril]

mts - reading through the thread, would love to mix up my own E6 regardless of colour balance, I enjoy experimenting