C-41 hand development for education setting

[jennifer_gioffre3]

Hello everyone,

I am the darkroom manager at a large university in rural NY. We have recently seen all of our photo processing local labs go out of business. One of our proposed answers to this problem is to develop our own film with c-41 chemistry by hand. The old tank and reels

way. I was wondering if anyone had suggestions. I am not interested in purchasing any type of rotary system, such as a jobo processor, I

would like to use just the tanks and reels that we already have in the darkroom. The chemistries that I have been researching are Kodak

Flexcolor,Trebla trelux system and arista 41. The information that I seem not to be able to acquire would be about replenishing the bleach,

and fix. One person suggested that we use each chemical once and throw it out when done. This I feel would possibly be a waste and I

would like to reuse as much chem as possible. Any suggestions would be greatly apprecaited. I am hopping that there is someone out

there that possibly has a previous experience with C-41 hand development in a large darkroom style enviorment.

Thank you!!!!!

Jen

[ronald_moravec1]

Due to the high activity of the developer and short developing time, it is necessary to drop the loaded reel into the tank

already filled with developer. All the components need to be at operation temp before you start including the tank, tank

top, chemistry, reel and film. Accomplish this by soaking the tank and top in 100 deg water bath and the reel and film go

into an empty tank for tempering.

 

It helps to keep the water bath stable if the bath sits on a styrofoam sheet or small feet so it does not loose heat to the

counter top. Keep a gallon of 150 deg water to keep up the temp.

 

The usual practice is to extend time rather than replenish for low column labs. About 4 oz per 80 sq in will be

sufficient replen if you go that route. The proper way is to season the developer and run control strips and check with a

densitometer.

 

Much luck if you think a bunch of students will be able to carry this out properly. I can and do do it. I also use a Jobo

and the Jobo performs all of the functions described which is why it was invented.

 

Agitation is 2 inversions every 15 sec as a substitute for continuous.

[subhash_tiwari]

Jennifer,

There has been a lively and very instructive discussion at RangeFinderForum.com, on precisely this subject.

 

http://www.rangefinderforum.com/forums/showthread.php?t=64785

 

As a consequence, I am awaiting my first batch of Tetenal C-41 kit from B&HPhoto in New York. Lets see what happens !

[edomazlicky]

Ron- so you are saying you can/should only process C-41 in a Jobo with Lift? Otherwise you would not really be dropping the film reel in the chemicals you would be pouring it and then putting the tank horizontal and mounting it on the machine. Just curious as I'd never heard that before.