C-41 developer capacity (one shot) - only 3 '120' films per litre?

[Tom Kershaw]

I realise this question has been raised before but I'd like to ask about safety margin. Putting my recent concerns about expired Kodak Portra 400VC to one side, I have generally achieved very good results processing 3 '120' films in 470ml of solution in the Jobo ATL-2300 using a Fujihunt kit.

In terms of checking through workflow, the Fuji instructions are not helpful so I turned to the Kodak Flexicolor documentation on the assumption that C-41 developers from Fuji or Kodak should be very similar. Looking at table 3-3 of document three in the series Z-131, I see Kodak give capacity as 3 rolls of 120 per litre of unreplenished developer (assuming 100-200 speed film), i.e. half the capacity that I'm working with. Is Kodak being conservative?

http://www.kodak.com:80/global/en/business/retailPhoto/techInfo/zManuals/z131.jhtml?pq-path=12338

Tom

 

[Tom Kershaw]

- any more on this?

Tom

 

[EdSawyer]

I use a SSK-4 (Phototherm) which uses 2 oz. (60ml) of solution per run, plus 3 ½ oz. (105 ml) per roll, so for 4 rolls of 120 it's using 480ml. I use it one-shot, with kodak C-41 chemistry.

-Ed

 

[Kevin Caulfield]

My experience is with the old Agfa C41 kits ("AP something") and you could easily develop four rolls of 120 in 500 ml, so in comparison Kodak do seem to be conservative.

 

[Tom Taylor]

I have been using the Kodak Flexicolor chemistry with a Jobo CPA-2 exclusively for close to 2 years now and alway got good results by following Kodak's instructions. If I want to process 2 rolls of C-41, then I'll mix enough developer (660mL) to develope those two rolls and toss. I'll mix enough bleach and fix for 1 roll (330mL - Kodal says you can process twice the number of rolls as with the developer without replenishment) and toss. If Kodak says to put starter in, I put starter in. If you use Kodak chemistry, you won't go wrong now or down the road by following their instructions. After all, they developed the process.

Developer is cheap - like $2.00 per Liter. If you mixed 1 Liter to process 3 rolls, your per roll cost for the developer is about 70 cents. Fixer cost is very little. The expensive part is the bleach and that's why you reuse it once.

Thomas

 

[Tom Kershaw]

Thomas,

It is here I can see the advantage of the Kodak chemistry sold on an a-la-carte basis, in that one can reuse the bleach while not over using the developer.

Tom

 

[srs5694]

FWIW, I replenish my bleach. I discard 70ml and replace it with fresh bleach replenisher per 36-exposure 35mm roll, as per Kodak's recommendations in one of their publications (I'm afraid I don't have a URL handy). This has worked well for me so far (no obvious problems), and it certainly helps keep the costs down.

 

[Tom Taylor]

Thomas,

It is here I can see the advantage of the Kodak chemistry sold on an a-la-carte basis, in that one can reuse the bleach while not over using the developer.

Tom

I think so.

Because of the oxidation introduced by rotary processing, Kodak recommends that you use the chemistry one shot and toss. However oxidation doesn't effect the bleach (in fact your are supposed to oxidize it before use) and you can reuse it up up to the stated limit (twice the number of rolls as the developer). Rather than saving the bleach and fix for another run at some other time in the future - which could be days or weeks away - I mix enough bleach and fix to process what I have at hand. That way my chemisty is always fresh. Also, unlike the bleach the fix is diminished by the aeration of the rotary processor so no use in saving it (and the final rinse) either for later. Developer, fix, and final rinse are cheap; it's the bleach that is the costly component.

Thomas

 

[Tom Kershaw]

I think so.

Because of the oxidation introduced by rotary processing, Kodak recommends that you use the chemistry one shot and toss. However oxidation doesn't effect the bleach (in fact your are supposed to oxidize it before use) and you can reuse it up up to the stated limit (twice the number of rolls as the developer). Rather than saving the bleach and fix for another run at some other time in the future - which could be days or weeks away - I mix enough bleach and fix to process what I have at hand. That way my chemisty is always fresh. Also, unlike the bleach the fix is diminished by the aeration of the rotary processor so no use in saving it (and the final rinse) either for later. Developer, fix, and final rinse are cheap; it's the bleach that is the costly component.

Thomas

I assume you're not using the final rinse as part of the Jobo processing programme?

Tom

 

[L Gebhardt]

I use 120ml of Kodak developer per roll in a Jobo. I use the fix and bleach for twice the capacity of the developer. Final rinse is done outside the Jobo tanks and I use the final rinse at the same rate as the bleach. While the fixer is cheap, you do need to dispose of it. Since I haul it to the hazardous waste pickup I try not to generate more than needed.

I've been using Trebla bleach.