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View Full Version : Low volume E-6 processing with Jobo CPP-2 & 3010



J.L. Kennedy
26-Oct-2004, 09:32
I own a Jobo CPP-2 with a couple of 3010 Expert Drums that I use for B&W processing. I would like to do some low volume E-6 processing of maybe 6-12 sheets every 2-3 months. This is not really a necessity as I can have the film processed locally for $3 per sheet but I was thinking that since I already have this equipment, I might as well use it for this also. I have the following questions: what would be a good choice of chemicals with regards to brand, size, etc.; the difference between 3 bath and 6 bath processes; shelf life of large volume kits v. cost of small volume kits; where to purchase in Los Angeles or via mailorder; anything else that might help me. I would actually like to do my own processing even if it cost a little more, just because I enjoy the activity.

Larry Gebhardt
26-Oct-2004, 10:40
I use the Tetenal 3 bath kits. You can mix up just the amount you need from either the 1 liter for 5liter kits. I make up 750ml at a time and develop 36 sheets with this (in a 2500 series tank). 500ml would let you do tw0 batches in the 3010 tank. 250ml should also work in your tank and let you do 10 sheets and then dump the chemicals.

I try to use up a 5 liter kit in 6 months and I spray in dust-off to displace the air. I have never had a problem doing this. I have no experience with any other kit, so I can't advise you there.

Pete Caluori
26-Oct-2004, 10:55
As Larry mentioned 3 bath does indeed work. I use Tetnal 3 bath chemistry as well, but I have used Kodak 6 bath chemistry. The difference between 3 bath and 6 bath is flexibility. With 6 bath you can tweak color shifts and really refine your process, with 3 bath you get simplicity, but not much room for tweaks. I've never had a problem with color using the 3 bath and that's all I use now, but it depends on your use. If you are doing critical color matching work you may need 6 bath chemistry, but from the question you posed I doubt that's case.

I use both the 3005 and 3010 tanks and I use 250ml of solution in the 3010 with 10 sheets of film. The final rinse should be done off the processor and I use a clean 8x10 tray, or Rubbermaid container for this. Tetnal's final rinse contains formalin and will keep a long time. If you will only be doing small amounts, you should mix 1 liter of final rinse and reuse it; it's very difficult to do a final rinse with only 250ml of solution. I usually use the 5 liter 3 bath kits and spray Protectan (which isn't imported anymore) but any inert gas would work.

Regards, Pete

CP Goerz
26-Oct-2004, 10:59
I have used both and found the capacity of the 6 step kits to be about 40% longer life. The three step is quite handy but keep a close eye on how many rolls/sheets you have developed and stick to the increased developer time carefully. Its best to store the chemicals in glass bottles, you can drop a few glass marbles in the bottles to keep as much air out of the solution if you don't want to buy the canned air.

CP Goerz

J.L. Kennedy
26-Oct-2004, 15:29
Thanks so much for the answers. The information about the difference between the 3 and 6 bath is particularly helpful because I won't be doing any manipulation of the color balance. I will also probably not be saving chemicals at the intervals that I plan to process so they will all be used one-shot. It sounds like I will be mixing 250mm at a time. Pete, how long does that final rinse with the formalin last in storage? Also, why is it difficult to do the final rinse with only 250mm?

Pete Caluori
26-Oct-2004, 16:31
Using the chemistry once (a.k.a. single shot) is the best way to proceed. The final rinse is a wetting agent and a formalin (formaldehyde) compound; as such it will last just about indefinitely. I know that I have kept it for 6-9 months between uses without any hint of a problem. There aren’t many containers that will allow you to hold a 4x5 tranny flat with just 250 ml of solution, so why cause yourself grief. Mix a liter, use it and reuse it; a liter has enough capacity to do way more than the 40 sheets you would put through it, assuming 250 ml per 10 sheets single shot.

There are several reasons why you don’t want to use final rinse in the Jobo drum. The biggest reason is formaldehyde hardens protein (one of the reasons it’s harmful to living critters, humans included) and gelatin the basis for the emulsion is a protein. Your 4x5 trannies will be curved in a semi circle in the tube and will “harden” in that state and they will be all but impossible to flatten. The second reason is Jobo does not recommend using any type of wetting agent in their drums, claiming over time these tend to coat the inner surface of the drum and cause problems. Lastly, the constant agitation will create more bubbles than a freshly shaken bottle of champagne.

One last point about using the final rinse… Depending on the film (Velvia being the worst that I’ve come across) some will come out of the Jobo drum very curved; this is all a function of the emulsion and the base. The emulsion on Velvia is quite thick and it swells considerably in the heat and moisture of processing. If you put them into the final rinse like this, they will remain curved forever. The film needs to be flat before putting it into the final rinse for it to remain flat. Kodak E100 films have a much thinner emulsion and remain flat when they come out of the drum. Whenever I process Velvia, Provia and Astia, I remove the sheets, reverse the curl and place them back in the drum where they can rest for a few minutes. If done carefully, with water in the drum, you won’t scratch the emulsion and the curl will come out of the film so that it’s flat.

Regards, Pete

mark blackman
27-Oct-2004, 04:22
I find the problem with curling can be reduced if you ensure your wash water is at the same temperature as the rest of the process, 38 degrees. Then, when you immerse the sheets into the stabilizer you can flatten each sheet out prior to drying. I personnaly use 500ml of chemicals in a 3010 tank and dump it - the cost of getting a shot far out-weighs the cost of processing. By the way, the foot pump makes lid removal a lot easier than trying to pull it off with your nails

Andre Noble
27-Oct-2004, 19:46
JLK, double your shooting.

tor kviljo
28-Oct-2004, 08:18
I have used the Tetenal E6 3-bath chemistry for years - buying it in 5 litres or 15 litres size. I use Tetenal Protectan gas to protect the first developer & color-developer concentrates from oxidations, and never have experienced the chemistry being exhaused. I use probably 1 - 2 of the 5 litres set a year, so one set may in fact have been opend for 8 months or so before the last part is use. At least in Norways, using the 5 litres set is GREAT savings compared to the small 1/2 or 1 litres set (don't remember the size - just calculated & found them hideously expensive). The protectan-spray - with heavy non-oxidizing gas - is expensive, but I still have my can from 5 years back - not empety yet! Cost pr. sheet is very minute - the best I do is 8 sheets 5"x7" in 0.3 litres using the 3004 expert tank on ATL-3000 - I guess I hit the maximum film pr- chemsitry volume with that combination - somewhat less with the 2509N reels & 4"x5". A 5 litre kit will do 50 reels 35mmx36 exp., but the chemsitry can take a good deal more than that if you mix it just before processing & use it one shot. This is because the chemistry (1 developer) is made strong enough to still give adequate prosessing after mixing, first use og up to 2 weeks of storage. During this use/storage process, some oxidation & reduced effect will take place. Using the developer fresh & as one shot, this excessive strength can instead be taken out in larger volume of developer. In a time when mony were shorter than today, I used 75 (or was it 70) % strength of 1. developer increasing development-time a little - worked out perfectly. The two other chemistries of the Tetenal E6/3b: the color developer & bleach-fix both go to completion, so when exceeding stated capasity og chemistry, just increase time on these two baths (ordinary 6 mins/38 celcius).