Gevachrome and orwochrome and E6

srs5694 · Jul 16, 2008

I did some Googling, at to my layman's eyes, it appears that Genochrome is CD-1. Specifically, this page specifies that it's "NH2.C6 H4.N(C2H5)2H2SO4 Diethyl Paraphenylenediamine Sulphate," which is what my notes (unreferenced) say is CD-1. See (there was a url link here which no longer exists) for information on where to get CD-1. I've got 100g on order, but it's back-ordered. I only need about 25g, so I'm willing to split my order with somebody else when it arrives, if anybody's interested. (US only; I'd hate to try to get this stuff through customs.)

Ian Grant · Jul 16, 2008

Genochrome (May& Baker) / Activol No 1 (Johnsons) is: N,N-Diethyl-p-phenylenediamine Sulphite

Ativol No 6 is: N,N-Diethyl-p-phenylenediamine Hydrochloride
CD1 / Ativol No 7 is: N,N-Diethyl-p-phenylenediamine Sulphate

Ian

Photo Engineer · Jul 16, 2008

And, those salt differences make a big difference in how they react in some formulations.

CD-3 is very weak and often requires benzyl alcohol or high pH to get the job done. The color developer above is probably about pH 10.0 and would be very low in activity with CD-3 for most films. The CD-1 would probably be the best choice. Genochrome has extra sulfite if I read Ian's post correctly. This will knock the Dmax of some films down due to competition by sulfite and you could get low Dmax.

PE

srs5694 · Jul 16, 2008

Hmmm... The page I referenced earlier specifies Genochrome is the sulphAte form, not the sulphIte form. I didn't find any other relevant references in a Web search, though, just mentions of uses of Genochrome. I have no knowledge of the issue beyond what I've read on the Web, so it appears that one source is wrong, but I don't know which. From where does your information come, Ian?

Ian Grant · Jul 16, 2008

Don't believe everything you read on the web. Genochrome is NOT CD1.

You can probably use CD1, CD2 or CD3 in the process in question but you would need to adjust the amount and pH to get the right balance to get the correct amount of colour development. One problem with some of these older processes is the Colour development isn't to finality so is quite critical.

The OP has CD3 so if he can use that it saves buying something else.

Ian

Photo Engineer · Jul 16, 2008

Ian;

You have a good point. The color developer formula above is very primitive compared to modern day developers which do go to completion and therefore the developing agent might be very critical.

PE

srs5694 · Jul 16, 2008

Ian Grant said:
Don't believe everything you read on the web. Genochrome is NOT CD1.

Unfortunately, I read both the Web site to which I referred earlier and your contradictory information on the Web. Please understand: I'm not trying to be a jerk or anything, but from where I sit, I've got two opposing claims, neither of which provides any sort of reference. You may be positive you're right, but unless you can provide more information, in my mind it's still 50/50.

Ian Grant · Jul 17, 2008

srs5694 said:
Unfortunately, I read both the Web site to which I referred earlier and your contradictory information on the Web. Please understand: I'm not trying to be a jerk or anything, but from where I sit, I've got two opposing claims, neither of which provides any sort of reference. You may be positive you're right, but unless you can provide more information, in my mind it's still 50/50.

The difference is I took the information from two reputable printed sources, not the internet.

From the British Journal Photographic Almanac 1961, page 134 - Colour Developing agents:

Genochrome /Activol - p-amino diethylanilineSO2 - Sulphite
Activol H - p-amino diethylaniline HCl - Hydrochloride
Activol S - p-amino diethylaniline sulphate - obviously Sulphate

The prices were all approx 5 shillings for 25grams, and the suppliers are listed.

In the 18th Edition of Developing, Focal Press, 1972, Jacobson lists 5 common Colour Developing agents, each with 4 of the possible ways of naming the compounds. This is the source for Genochrome in the previous post.

In full Genochrome is:

Diethyl-p-phenylenediamine sulphite
N.N-Diethy-p-phenylenediamine sulphite
p-Diethylaminoaniline sulphite
4-Amino-N,N-diethylaniline sulphite
p-amino diethylanilineSO2
(C2H5)2N-C6H4-NH2.SO2

You will see that Johnsons made all three salts.

Activol (No 1) - sulphite
Activol H (No 6) -hydrochloride
Activol S (No 7) - sulphate

So Genochrome is not CD-1.

Ian

Photo Engineer · Jul 17, 2008

I might add that the sulfite salt keeps better, and if you look at Kodak kits, all CD-3 and CD-4 is packed as a liquid concentrate of the sulfite now, so you literally cannot call them CD-3 and CD-4 for the same reason Ian shows above.

PE

Ian Grant · Jul 17, 2008

I know had some in my stash of Colour developing agents.

Ian

srs5694 · Jul 17, 2008

Ian Grant said:
The difference is I took the information from two reputable printed sources, not the internet.

From the British Journal Photographic Almanac 1961, page 134 - Colour Developing agents:
...
In the 18th Edition of Developing, Focal Press, 1972, Jacobson lists 5 common Colour Developing agents, each with 4 of the possible ways of naming the compounds. This is the source for Genochrome in the previous post.

OK, thanks. That's why I asked. Your earlier posts didn't mention any specific sources for the information. Yours seems to be more authoritative than the Web page I found, which only says they got the information from Retro Photographic. Probably there was a typo somewhere along that particular information chain.

Ian Grant · Jul 17, 2008

Might have been Nigel Dear's typo, although I can't find CD1 or Genochrome on his site (Retro Photographic)

I suppose it's my University training which emphasised the importance of consulting Primary sources which means I always counter check formulae etc I've found on the Internet. The classic for not checking Primary sources is Ryuji Suzuki, when he quotes from them it's because he's copied the quote !!!

Ian

narigas2006 · Jul 21, 2008

Back on the CD's, So, I just checked artcraft chem list and they had either CD2 or CD3, I suppose CD2 would a be better agent for the color developer, right? And other very stupid question, if I put more of the CD3 agent, would it makes any difference (to compensate for the weaker action)?

Many thanks!!!

Richardson

Ian Grant · Jul 21, 2008

There seem to be two variables with these older Colour developers, the quantity of developer and the amount of carbonate.

Compare the 1954 & 1961 Colour developers

1954 Colour Developer
Genochrome 2g
Sodium Carbonate (anhyd) 37g
Sodium Sulphite (anhyd) 3g
Water to 1 litre

1961 ColourDeveloper
Droxychrome 1.5g
Sodium Carbonate (anhyd) 74g
Sodium Sulphite (anhyd) 1.5g
Water to 1 litre

So if you use CD2 or 3 you'll have to arrive at you own balance.

Ian

narigas2006 · Jul 21, 2008

But just to go in the right direction,

more active developer requires more or less carbonate?

Ian Grant · Jul 21, 2008

Less active I'd assume, but they may act best at different pH's. You'll have to try it and see.

Ian

Photo Engineer · Jul 21, 2008

narigas2006 said:
But just to go in the right direction,

more active developer requires more or less carbonate?

To be more specific, if you wish to make a more active developer solution with the same ingredients then you must increase pH. Often, adding more carbonate does not increase pH, it just improves the buffer capacity. So, you would change from Sodium Carbonate (pH ~10.0) to a Sodium Phosphate mixture (~pH 11.0).

PE

Ian Grant · Jul 21, 2008

The problem is going to be these Agfa based films & processes are notoriously finicky, far less tolerant to deviations from time & temperature etc compared to E3/4.

Then how will the age of the film affect the results, it's a case \of suck it and see.

Ian

Photo Engineer · Jul 21, 2008

And I would add, referring back to your previous post Ian, that the color developers are incredibly unsophisticated. The complex nature of the E series color developers was one of the things that helped damp things out by developing to completion. This was the entire idea behind the Ektachrome process based on the problems you observed with these obsolete films.

Basically too, these films were made by combining 3 B&W emulsions, but the Ektachrome and Kodachrome series used emulsions tailored just for reversal processing. Such an emulsion is usually finished into fog as we say at EK so that the development to completion is assisted by the film. It also has excess coupler and uses the silver level to govern Dmax.

PE

narigas2006 · Jul 22, 2008

I have to say that I am getting more than I expected with the CD4 developer... Also, could I crank up the pH with NaOH or KOH in the case of the CD3 formula? Other thing, how the gevachrome process differs from the ME-1 (the old ekta process)? Thanks!

hectorpaljr · Jul 22, 2008

Colour dev

Have just picked up this thread after searching for Colour Reversal Club.
I recall that phenidone was an alternative color agent (dont know the formula) . I think that the old Ferrania process will develop the old Geavart and Agfa product. Certainly the agfa chemicals were used commercially by one lab in the Uk to develop Ferrania in the 1970's.

I processed Ektachrome E3 in Ferrania chemicals with success in the distant past.

Photo Engineer · Jul 22, 2008

Phenidone is not a color forming agent of any sort. It is used in many B&W developers.

PE

Ian Grant · Jul 23, 2008

Phenidone was used in one of the 3M/Ferrania colour formulae, and it was possible to use it in place of Metol for E3 processing., but of course this is in the First developer, not the second colour developer.

Munns Brothers, a large professional lab in Birmingham UK, made all their colour chemistry from raw chemicals until they closed the lab, the owners had diversified and they now own a large chain of UK High Street minilab outlets. I think they ran an Agfa line.

Ian

hectorpaljr · Jul 23, 2008

Thanks for correction re: phenidone. My memory is clearly failing! (Its 35years since doing the processing). Interested in your comments re Munns, Ian, - I only used them once via my local chemists and for ektachrome processing. The fact I only used them once says it all really - that memory of 40 years is still quite vivid even if the slides were not.

hectorpaljr · Jul 23, 2008

Have just seen on Ebay a British Journal of Photography annual 1971. It contains formulae for all transparency processes at that time including Ferrania, Agfa , Orwo etc.

Gevachrome and orwochrome and E6

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