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View Full Version : Jobo CPE3 + Tetenal C41 2.5L yields



artcorr
18-Mar-2018, 21:00
I'm considering starting to develop my own 4x5 C41 and trying to do the cost calculations. I'm looking at getting a Jobo CPE3 (or used CPE2) and developing with Tetenal 2.5L kits because they're the easiest to get where I live. I've been trying to do the maths on how many sheets of film I can get out of a kit and would love if someone with experience could let me know if this is right.

With the 2550 tank it looks like I'd be using ~600ml of chemicals for 12 sheets, so I'd get 48 sheets from the 2.5L kit?

artcorr
18-Mar-2018, 21:06
Also is there any possibility of reusing the chemicals for another batch or should they go straight down the drain?

koraks
19-Mar-2018, 01:28
In my experience, c41 chemistry wears out more by aging/oxidation than by use. With heavy use, extending development time is sometimes recommended to make up for loss in activity of the developer. I personally use c41 one or two shot with a minimal volume in a jobo 15xx or 25xx. 150ml in a 1510 therefore easily develops 2 rolls of 35mm, which is equivalent to one 8x10 sheet. 8 sheets of 8x10 in 600ml should still work fine, although it's probably pushing the boundaries.

Bernhardas
30-Apr-2018, 18:09
I'm considering starting to develop my own 4x5 C41 and trying to do the cost calculations. I'm looking at getting a Jobo CPE3 (or used CPE2) and developing with Tetenal 2.5L kits because they're the easiest to get where I live. I've been trying to do the maths on how many sheets of film I can get out of a kit and would love if someone with experience could let me know if this is right.

With the 2550 tank it looks like I'd be using ~600ml of chemicals for 12 sheets, so I'd get 48 sheets from the 2.5L kit?

the kit is rated by Tetenal for 16 films (16x4= 64 sheets) per liter (with increasing time, and reuse).
I usually mix 1 l from concentrate and re-use until exhausted. Within five days after mixing that works for me. The open concentrate is covered by protectan and stored cool so it keeps about 3 - 5 months.

In your scenario 600 ml should be good for 36 sheets by reusing it three times. By mixing four batches the kit would yield 144 sheets.