C-41: Necessity of stabilizer. (Also E-6.)

[srs5694]

Hi,

I've been doing my own C-41 for a few weeks now, and I thought I'd revisit a question I had when I started but that was never answered to my satisfaction: How necessary is stabilizer? According to this Kodak page, stabilizer is unnecessary with most modern Kodak films. Is this really true, or is Kodak being optimistic? Is the claim about no need for stabilization dependent upon using Kodak chemistry for the rest of the process? What about non-Kodak films? If stabilizer really does no good, I'll eliminate it in favor of the "final rinse" product, which has no formaldehyde, and save myself some safety issues.

I'm also interested in answers to these questions for E-6 films. Also, if using stabilizer is still a good idea, are C-41 and E-6 stabilizer interchangeable? (I'd rather cut down on the number of bottles in my cupboard, if possible.)

Thanks for any advice on this matter.

 

[Photo Engineer]

The final rinse in that web page is a stabilzer to use in 'washless' processes and minilabs. It can only be used on modern films, as the stabilzing agent in it is not effective in older films. It is optimized for washless processes which leave a lot of the fixer in the film along with silver salts.

The older stabilzer is preferred if you have a process with the full wash, as it will treat all film versions for optimum dye stability. In fact, IMHO only a process with a full wash will give the optimum stability to your images.

Read the warning at the bottom of the web page you refer to.

E6 and C41 use different stabilzers. Please read the MSDS on the packages and also note that the conditioner in E6 aids in stabilzation, whereas C41 does not use it.

PE

 

[jd callow]

The final rinse in that web page is a stabilzer to use in 'washless' processes and minilabs. It can only be used on modern films, as the stabilzing agent in it is not effective in older films. It is optimized for washless processes which leave a lot of the fixer in the film along with silver salts.

The older stabilzer is preferred if you have a process with the full wash, as it will treat all film versions for optimum dye stability. In fact, IMHO only a process with a full wash will give the optimum stability to your images.

Read the warning at the bottom of the web page you refer to.

E6 and C41 use different stabilzers. Please read the MSDS on the packages and also note that the conditioner in E6 aids in stabilzation, whereas C41 does not use it.

PE

PE,
If cross processing E6 materials in C41 chems should the stabilizer be the C41 or E6 version?

No waffling mister

 

[Photo Engineer]

No waffling whatsoever!

Since the color developing agents are not right in the first place, not even the dyes being formed are the right dyes, therefore it wouldn't really make much difference which stabilzer you used. I would go with the process stabilzer just to try and approximate the right conditions.

CD4 dyes are quite different than CD3 dyes.

PE

 

[jd callow]

So the stabilizer is dependent upon the process more than the dyes? Or have I just begun a circular argument that can have no resolution?

 

[srs5694]

Here's another question: I was spurred to post my original query because of a recent thread on the Usenet rec.photo.darkroom newsgroup. Somebody there has suggested using this as a formaldehyde-free stabilizer:

water: 800ml
glyoxal, 40%: 3ml
Photo Flo 200: 0.8ml
water to: 1l

I'd be interested in hearing opinions on this, particularly from PE. Thanks.

 

[Photo Engineer]

Perhaps yes and perhaps no.

Actually, the stabilzers are there for both the residual couplers and the dyes that formed. The coupler can react with dye and can also react with itself. Formaldehyde prevents this. Hypo and silver salts left in the film do other things, as does having the film at the wrong pH. Colored couplers in negative films are different than residual non-colored couplers in E6 films IIRC.

It is truly complex chemistry and different for each dye set to some extent.

But then I waffle. I hope this was exactly the answer you wanted.

PE

 

[srs5694]

Just a bump on this -- I don't think PE saw my query about using glyoxal in place of formaldehyde. Is there any merit to this suggestion? Thanks.

 

[Photo Engineer]

NO.

AFAIK, glyoxal does not have exactly the same reactivity with the coating chemistry as formaldehyde does.

If that were so, then glutaraldehyde and succinaldehyde could also be recommended. I think that EK would jump on it if it were true. Feel free to mention this over there on the other site as well.

I never ran across any other aldehyde that did the trick in this regard like formaldehyde. It must form what is called a 'methylene bis coupler' to help prevent yellowing and the formation of leuco dye. That takes the form of two couplers attached together by a formaldehyde molecule with the elimination of one molecule of water IIRC. Nothing else does the job. The other aldehydes harden gelatin, but don't react in the same way with the couplers.

Sorry.

PE

 

[srs5694]

Thanks, PE. I won't experiment with gyoxal, then.