Two months in, I've been thinking about my process and costs, and am ready to share. A lot of people wait a month or two until they have 10 rolls and soup a big batch. For me that doesn't at all fit my creative process. I thought I'd share how I got here.
Started with an Arista kit, bought locally at Freestyle for $27.99. I went in knowing that I wanted to go with Kodak chemicals, so this test kit was really to see if I was going to be able to deal with C41. I liked C41 but the kit didn't really match my workflow - I felt pressured to really shoot a lot and use all the chemicals in a week, two weeks tops.
Kodak chemicals to make 5L dev / 5L fix / 5L final rinse / 10L bleach iii = ~US$130 shipped. I have a lifetime supply of acetic indicator stop, so I'm not bothering to include in the calculation.
My C41 volume is 1 120 roll / week, sometimes 2x120, 1x 35mm, up to 6 sheet 4x5. I shoot and process the same or next day, and spend the rest of the week printing RA4 in room temperature trays.
The results combined with ra4 printing (yes, at home in trays) is astonishing. I've never been happier with the results.
My start up costs coming from a decade or so of b/w:
5x Astropaq 3L disposable wine bags, about $2 each
Wine preserving gas, $10, I use for concentrates and (larger) RA printing solutions
Anova Sous Vide $120 - circulates water and maintains temp for the crucial developer temp step. I do use it for food so chemicals go in a metal bowl - kind of hard to explain but the gist is the anova doesn't get contaminated. I had tried modifying a $20 aquarium heater to reach 100F but it was a total bust.
I'm replenishing the developer solution with replenisher at the rate specified in the Z manuals. Then after 8 weeks I'll discard the developer and make a fresh batch. I don't discard the bleach / fix / final rinse, just replenish using the Z manual starting points. They talk about using process control strips, which seems overkill to me.
For the developer, I mix up 1L replenisher, which is sufficient to hand process in a jobo 4x5 tank, and twice what I need for 2x35 or 1x120.
The replenishment rates as published:
Developer: 11.2mL per 4x5 sheet, 33.1ml per 35mm (36 exp), 37.8ml per 120.
Bleach, fix, final rinse: 17ml per 4x5, 66ml per 35mm, 66ml per 120.
Cost breakdown 1st 8 wks / per roll
Dev $2.80 / $0.35
Bleach $5.60 / $0.37
Fix $2.40 / $0.16
Final Rinse $1.00 / $0.07
Total $0.94 per roll.