Final Answer on 3 vs 7 bath E6?

I've been searching around the archives and reading the various threads about E6 kits, and I'm still not sure what the consensus is regarding the quality difference. Obviously, 3 bath is cheaper, and I understand there may be some long term stability issues related to it. (is this true if I still use Kodak C41 final rinse?). However, the economics of 3 bath at this time cannot be denied. I have just set up my Phototherm with a Fuji-Hunt kit, and I'm really liking the results. However, I am concerned that my working solutions will expire before I can use all of it. I'm using "Protection Spray" and I expect to get about 4 weeks out of the developer. The other chemicals I assume are similar to C41 in their long term storage. Still, the Fuji Hunt kit is extremely expensive. I just opened up a small scanning and developing lab here in Portland Maine (Dead Link Removed) and offering E6 is pretty important to me.

TL/DR : What's the low down on 3 bath vs 7? Is there an image quality difference, or just a theoretical stability difference?

Also, why is it so hard to find Kodak E6 chemicals? Unique Photo only has a few, it seems you can't just buy what you need like I do with Flexicolor and you have to rely on these kits...

Basically, the 3 bath kits use blix, not separate bleach and fix baths. Blixes can be shorter lived than separate baths and might not always be as effective. This could leave you with retained silver in your film and higher minimum density. These kits have stabiliser bath that takes care of image stability, so that shouldn't be an issue. C41 final rinse is probably not a good idea with 3 bath kits.

AFAIK, Kodak doesn't make any E6 chemicals any more, so what's there is old stock. Of course, this might change with the reintroduction of Ektachrome E100.

So I could theoretically end up with higher density? Perhaps extending the Blix time would mitigate this issue? I suppose I'd have to run some tests. I'd love to keep running 7 bath but right now the economics of it are not great...

Ron Mowrey, who was deeply involved with the development of BLIXes and bleaches for color processes, has stated on multiple occasions, that cost effective BLIXes are unable to completely remove all the silver from color film products. There are two forms of retained silver:

1. retained metallic silver from incomplete bleaching leads to off colors and reduced saturation, increased grain and in case of E6 to increased Dmin.
2. retained silver halides from incomplete fixation can and will react with Hydrogen Sulfide in air, which leads to brown and uneven discolorations.

X ray analysis methods are required to reliably and quantitatively measure retained silver, therefore you should not expect credible updates to Ron's statements here on APUG or elsewhere.

In this regard, you may well consider Ron's disapproval of three bath kits as "final".

Rudeofus said:

Ron Mowrey, who was deeply involved with the development of BLIXes and bleaches for color processes, has stated on multiple occasions, that cost effective BLIXes are unable to completely remove all the silver from color film products. There are two forms of retained silver:

1. retained metallic silver from incomplete bleaching leads to off colors and reduced saturation, increased grain and in case of E6 to increased Dmin.
2. retained silver halides from incomplete fixation can and will react with Hydrogen Sulfide in air, which leads to brown and uneven discolorations.

X ray analysis methods are required to reliably and quantitatively measure retained silver, therefore you should not expect credible updates to Ron's statements here on APUG or elsewhere.

In this regard, you may well consider Ron's disapproval of three bath kits as "final".

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How much of that is theoretical vs practical? Would a 3 bath kit have off colors, increased grain, and discolorations each time? A film could have increased grain, but not perceptibly, for example...

I just popped in to wish you the best of luck with your lab. I enjoyed looking and reading your website.

It is always good to see a film process service available.

Thanks! I've gotten up and running but it's still early days. Luckily must customers have been happy so far. New England needs a lab that takes film seriously and I am to do that.

Sperdynamite said:

How much of that is theoretical vs practical?

Click to expand...

Unfortunately, it is impossible to say. High speed (high iodide) films are much harder to blix than low speed films. A fresh blix works much better than one that is even a few hours old. All steps in E6 except the first developer are "to completion", so you can always add double, quadruple or more (within reason) the blix time. Problem is you don't know if/when blixing is complete. Problems in processing may not manifest themselves for several years.

If you search the resource section, Rudi has very generously shared a process for making a separate bleach/fix out of a blix kit. You will need a pH probe, but it is not difficult. This might be helpful if you are having difficulty accessing a 7 bath kit as I have.

All the best of luck with your lab. I hope you find an acceptable solution.

All of the answers above touch on the correct information in some way or another. It may indeed take years to see changes, and E6 does need Formalin in a stabilization step at some point in the process to improve stability above anything caused by retained silver.

PE

Hard to know where best to post this in the many E6 threads but a supplier in the UK I use a lot for "odd" films is taking on stock a six bath E6 kit:
https://ntphotoworks.com/shop/product/bellinifotos-proper-six-bath-e6-kit-1lt-new/

Data Sheet:
https://ntphotoworks.com/shop/wp-content/uploads/2017/03/KIT-E6-1-lt-NT-English.pdf

No overseas shipping I'm afraid, regulations.