They don't last long...you need to mix them up & use them ASAP. Kodak puts a date code on their packaging because the concentrates don't last forever either. With E6 there are too many variables--almost anything can & will go wrong eventually. I run E6 in our lab using a Wing Lynch processor, an Intellifaucet, Kodak 6 step kits, control strips etc and even though the processor is automatic, the actual process is anything but that. You need to have very good habits when you use E6--like consistent mixing and be very clean as well--contamination is a big problem. You need to do everything like a robot--the same way every time, so when something goes wrong & you start to troubleshoot, you can do it by process of elimination.
Lucky for you though, Kodak has now made the Z119 manual, the E6 book , available free online. Here's a link:
FWIW, you won't get the control charts with this online version, but if you're not running control strips, you won't miss much there anyways....
I had come up with about a zillion tips for setting up your process, but I couldn't seem to narrow them down....but I will quote a Kodak tech who told me that "not all E6 is E6", and I'll add that not all chrome films run the same way either. The 6 step kits are second best, and a replenished line of chemistry (the "real" E6) is the best. In a one-shot process, by the nature of the beast, there isn't as much control as in a replenished line. With the 6 step kits, you can tweak the steps by pH, specific gravity etc for your process. But I wouldn't recommend reusing those Kodak 5 liter kits. They were made for one-shot use and there could be problems--in fact, I don't see how there *couldn't* be--but I have never reused them, so YMMV.... We use over 5+ kits a week though as one-shot. Our cost is actually the same as that of our local Q Lab. What we get is more control--not neccesarily convenience though because there's the constant headache of maintaining the machine and mixing up all that chemistry. The only step I think you might could reuse would be the bleach--but you would have to aerate it. Whatever you do, DO NOT wash between the color developer and pre-bleach. This used to be called "conditioner" and still is in fact in some kits. Kodak E6 changed several years ago for formaldehyde free compliance. The stabilization part of the process in the 5 liter kits, is now done in the pre-bleach step and is triggered by carryover color developer. If you wash between these steps--as you once did with the previous kits--you will compromise the longevity of your film. The colr developer is used to completion in the process too, it's pretty much shot afterwards.
No matter what chemistry you use, you'll probably need some sodium hydroxide 5N or sulfuric acid, or even both, to tweak the pH of your color developer. Kodak films go on a blue/yellow bias with the pH of the color developer--Fuji films shift magenta/green. My advice would be to pick one film and learn how to process it first, since all films like something a little different....we use longer final washes for instance with our Fujchrome, or else they tend to run magenta--coupled with adding alot of sodium hydroxide to the c.d. The new chrome films don't like pre-wets or any pre-heat using water...so you need a process that uses a dry pre-heat somehow, even if it's a tube and a hair dryer.....the temperature of the early steps is very critical, so even something like a room temp stainless reel can throw off the temp in a tank or a tube.
Hope this isn't too confusing and have fun if you gotta do it at home, otherwise do what I do at home--send it out!
BTW--E6 isn't going anywhere... your best bet will be either a Kodak Q lab or a Fuji Oasis Lab. Even the best labs can have off days too......
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