No, you're not (entirely) off the ball.
Originally Posted by StoneNYC
Let me reiterate that I have no experience with E-6, which is what you are asking about. I have SUBSTANTIAL experience with the color neg/paper processes, which are fundamentally similar to your color developer.
Here's what fundamentally happens to color developers: 1) when you develop film: you build up by-products, mainly DIRs and various halides, which may tend to slow down development, and 2) from just sitting, somewhat exposed to air: the preservative package is somewhat degraded, perhaps a small amount of developing agent is oxidized, there is some evaporation, and probably a slight pH shift.
In the case of E-6, color developer follows another solution, so there is additionally a substantial dilution of tank components due to the carry-in from the film, which does not normally happen with the color neg systems.
Replenisher counteracts ALL of these things, but the proportions are exactly correct only for one specific aim condition. If you are developing film, with only slight exposure to air, the replenisher should be very close to ideal. If you have a lot of down time, with air exposure, things go slightly off-kilter - you lose mainly preservatives, and slightly developing agent; adding replen gives both. You need to add some volume to counter the evaporation and dilute the byproducts, but replen will tend to overdo the developing agent. So you might try half water and half replen - I'd say this is a pretty fair guess. Processing a control strip will let you know if you're close or not. If you could find a replen designed for low process utilization, it would be similar to the latter, except that it would not overdo the developing agent so much.
Regarding the question, "is this worth doing?" I don't know. If you're buying your chems in the form of replenisher and using "starter solution," then you already have replen - in this case, likely worthwhile. (You also have to take on the additional job of verifying that the process level is ok.) If you don't already have replenishers, likely not worthwhile.
I don't know if you'll believe this, seeing as how a couple of hi-level chemists are taking a contrary view. So if you need me to argue with them, let me know. I'm not even a chemist, but my real-world processing experience (outside of E-6) is very substantial. I've overseen setup and operation of developer regeneration equipment for EP-2, using ion-exchange columns to remove bromide, with full chemical analysis to determine the regen formulas (from components), bleach-fix regeneration systems with silver recovery with custom regeneration formulas, etc. So I have a good sense of how these things vary in different operating situations.
Last edited by Mr Bill; 04-14-2013 at 03:08 AM. Click to view previous post history.