C-41/E-6 processing with my Jobo ATL-2300 processor
I paid over $2000 for this processor about 8 years ago and I have had more processing failure than simple manual tank inversion method with simple water tempering bath I did for many years before I got the Jobo processor. I was very excited to get the processor but it was like cold water pouring over my head when I first tried to process E-6 for a few rolls of Velvia 50 back then. I stopped processing E-6 due to much higher cost and before finding out what caused the process to fail but I continued with C-41. I found I was'nt able to process two 220 rolls in one processing run. The results were poor and I wasted a lot of films and chemicals.
I ended up to process only one 220 roll at a time with 850 ml of developer (bleach and fix as well). The result was better but I never felt great about it. I pretty much concluded that Kodak C-41 developer's capacity is 1 roll of 220 per liter and this is documented in Kodak Z-131 tech pub. Jobo ATL-2300 tank capacity is 1 liter. So I pretty much determined that despite it is a huge machine it can not process more than 1 220 roll at a time. Mean while I kept on hearing people saying they are able to process a roll of 220 with as little as 300 ml +/-.
Then I saw a suggestion from PE to pre soak (with 100 degree water) before the development step. If I remember correctly he even suggested pre soak twice. Man, this was like light at the end of a tunnel. What did he mean by that? He was referring to processing with Jobo processors. I think PE made this suggestion many times before many years ago. It was only when he said to do it twice that hit my head and woke me up...
I ran a processing drill with my ATL-2300 with no films set up with two pre soak steps before the development step. This is C-41 that I am talking about. I waited patiently by the processor. When the processor drained and collected the first pre soak water I measured the temperture of it immediately. It was 96-97 degree. The 2nd pre soak water came out to be 98-99 degree. I was stunned. What if there were films in the tank, especially with 2 rolls of 220? The process would have failed no doubt.
I immediately started a series of testing with real 220 films. I started out with 850 ml still and programmed two steps of pre soak with 100 degree water before the development step. Sure enough I shouted out bingo when I looked at the result. All were perfect. I continued with several processing runs, each with 2 rolls of 220 and the last two processes with only 630 ml of developer. The result were still perfect. I have not done it again with the next trial with 560 ml yet. I am pretty happy with 630 ml now.
What a difference these two pre soak steps made!!! I finally realized that Jobo rotary processing has this problem that the films really need to be pre soaked with tempered water or when the developed is poured into the cold tank the process will fail. I was able to do one roll of 220 with 850 ml before because the volume of the developer was quite large so the temperature did not drop too much. Now with two steps of pre soak I can do two rolls of 220 with as little as 630 ml of developer.
I feel that I need to say a few words here to thank PE for his great contribution to this forum. Thank you so much PE. With your tips I finally solved the problem.
Jobo ATL processors have 6 tanks only. So this may be a problem for E-6 processing. You can't use any of the tank for pr soaking the film. But I realized that you can still program it to rinse the film before the process starts. The rinse water will have to be tempered at exactly 100 or slightly higher than 100 degree. I will have to set up a tempering bath to provide tempered rinse water for my ATL-2300. This will take some time so I won't be able to try E-6 soon but I definitely will want to do it in the near future.
My next goal is to process 4 rolls of 220 with 1 liter of developer. I hope the developer has the capacity of 4 220 rolls per liter. If not I am sure it will do 3 rolls at a time.
Well, Kodak tech pub for C-41 does not specifically say anything about pr soaking. When I manually develop my films I never pre soak the film. I don't remember ATL-2300 manual recommends pre soaking. In fact I had to pre soak twice to be enough (thanks to PE to point that out). I tried to pre soak once but the result wasn't too good still. By the way, ATL processors are different from all CPA or CPE processors. You have to program to use one (or two) of the 6 chemical tanks for pre soaking on ATL processors. That is not possible for E-6 process that needs all 6 bottles for chemicals, leaving no tank but to use rinse water to pre soak. There is no tempered rinse water on all ATL processors. You will have to temper the rinse water with a separate tank pressurized like tap water.
ATL processors can be programmed to pre heat the film tank by rotating the drum with only films in it. It never worked for me. I tried to pre heat like that for 15 minutes and the profess still failed. That's why I never though pre heating (effectively) or soaking would make a difference.
Rotating an empty tank in a warm water bath gets you a warm tank and "cold" film!
You need the presoak! At least 2 of them even though one is better than none! I've said that over and over and most people ignore or dispute the results, but you have the data that proves it. And, BTW, you can overdo it as well. But that is another story. Don't use 5 or 10 mins of presoak. I have done that due to interruptions and it is just not "perfect" .
Thanks so much for the kind comments and the vindication of my suggestions with proof!
The Kodak E6 documentation for rotary processing advises against pre-soaking apparently due to potential for process inconsistencies.
Originally Posted by Tom Kershaw
With all due respect, "pbllt" as Bill the Cat would say. Sorry.
No disrespect intended!
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How much and how long for the pre-soak under E6
Surprise me a bit as I do not even question this part, just dogged follow the Kodak instruction. I did not that I cannot develop too much 120 E6 slides in one go but I guess it is just me.
Originally Posted by Photo Engineer
With that, may I ask for some advice:
- any difference between black&white \ E6 \ C41?
- how long should I presoak it? (1 minute?)
- how much volume of liquid? (same as normal development volume?)
- how to do it? (let it rotate like an extra 2 step? or put it 100F water seperate from the jobo and fill the tank up for a certain time ...)
- would it be the same for expert drum and normal print/film drum? (I have quite a lot of different types of drums. In fact I still have not start my 8x10 using expert drum yet as I find no ease way to open it so far; use print drum for that normally with 50%-80% works ok. Development drum for 4x5, 135 and 120.)
- would it be the same for ATL1500 and CPA2 (in fact I have two more an old CPE2 and an Duolab)?
Sorry so many questions as this line of question is really a surprise to me.
BTW, I guess under ATL1500, one may have to do a seperate process for presoak ..., assume it as an 2 steps now.
Thanks in advance for the advice.
Last edited by dng88; 08-30-2010 at 12:11 AM. Click to view previous post history.
Steve, I do have the original ATL-2300 manual. I do not get the impression (unless I read it all over again) that it recommends pre-soaking. It has the pre heating feature built in by rotating the drum over the water bath for any period of time. As PE pointed out it won't heat the film but the drum. This feature does make you think that pre-soaking is not necessary if the film is pre-heated. Wrong. I have had too many processing failure all because of this. It may work fine for a roll of 120 or 135 film. But for two rolls of 220 it never worked for me.
PE, it was exactly what you said to pre-soak twice that woke me up to think of why you said twice? I also saw your note: Rotating an empty tank in a warm water bath gets you a warm tank and "cold" film! that's when I suddenly realized completely what was really the cause of my processing failure. I have since done more than a dozen rolls of 220 with two pre-soak step and there was not a single failure yet.
I have not done many E-6 on my ATL-2300 yet. But the ones I did was not anything to brag about. I blamed on the chemical's capacity (not enough for the amount of films I put in). I believe it had something to do with cold films in the drum too. If Kodak does not recommend pre-soak for E-6 for the reason of processing consistency I am willing to try pre-soak (with rinse water)still. As long as I do it every time there should be no consistency issue for me.
Dng88, the question to pre-soak or not for the expert drum may depend on how much film you have in the drum and how much developer will be poured into it. If there is much film in the tank and very little amount of developer is used you can anticipate that the developer temperature will be lowered significantly if the film is not pre-soaked.
My method is to use just about as much water as I would developer. I dump it into the rotating drum and then empty and pour in another dose of water at the same temp. (I have 2 containers of hot water ready for this but I can fill a fresh container if I'm quick enough.) So, it is pour in while rotating and dump then pour in while rotating then dump (making sure this second dump drains very very well) and then dump in developer and start the timer. (I have an auto timer on my Jobo that starts the clock when I dump)
The drain is critical. I think that many people who try this don't drain well. That is a problem. Also, some use 1 or 2 minute prewets and that is actually going too long. It is pour and dump.
I use the same method with B&W film but the prewet is 20 deg C!
I believe that with E6 you may have to increase the first developer by about 30" but I'm not sure with recent films Sorry. If they are dark, that is what you must do. The E6 first developer is a tad quirky, the C41 developer is not.
I had no problems with dry prewarm, but I've been preheating at least for 5 - 10 minutes. Eventually, the film inside also gets warm, but it may take time and is hard to control.
But, as per PE's suggestion, I've also moved to two-step prewash, and this has made my process much more quick and removed any uncertainty I had with dry prewarm. I use something like 5 + 15 seconds.
Pour and dump is easy for an ATL processor. But to drain thoroughly it is a problem. The processor gets only 20 seconds to drain. Fortunately this seems OK if I process two 220 rolls at a time with 640 ml of developer. The developer is not diluted enough to really impact the result I think. My negatives have plenty of density and contrast. There is no color crossover. The colors came out of my scanner look just right without any adjustment. I may have a problem if I only process a roll of 135 with 250 ml of developer.
Jobo processor starts to count down from 3 min 15 seconds as soon as pouring of the developer begins. Draining also begins about 20 seconds before the count down reaches 0. Before I had the ATL and process manual I always press the button of the timer after pouring the developer. I think I began to drain the developer a few seconds before the timer reached 0. I think this 5 - 10 seconds difference is not noticeable considering the latitude of C-41 films.
Before I began the practice of the two step pre-soak I often got color crossover problems and coarse grain. There was enough density on the film. The negs were very difficult to scan. Always needed color adjustment. Histogram would show RGB layers got uneven development. Usually the Magenta is lagging behind R and B (too much green). Well, this is what I saw on one recent roll. If I used 850 ml of developer to process one 220 roll would get OK result. What a difference the two step pre-soak has made. This really tells how critical developer temperature is for C-41.
Last edited by mtjade2007; 08-30-2010 at 03:52 PM. Click to view previous post history.