Need advice regarding Jobo CPP2 and C-41 developing: something's wrong..

[MWitmann]

Hi all,

recently i've bought with a friend a Jobo CPP2, in order to gain our independency regarding the C-41 color development.

We've managed to start the process with good results, developing around 100 4x5 sheets, but after the scan we saw a problem on some negatives.

Inspecting the emulsion side of the negatives, we saw some white spots, in some case having the shape of a splash. Consulting the Tetenal C41 manual we identified the problem as "milky spots", probably resulted from not enough bleaching.

Before the batch of 10 sheets in which we reported this problem, in the same day, we've developed other two rounds of 10 sheets each, whitout reporting any problem, using exactly the same chemicals (fresh) and steps.

We had in the Jobo expert drum 8 portra 400 and 2 ektar, and the portra were the most affected by this problem. After seeing the spots we washed the negatives for several minutes, and after that we performed another bleach (as suggested in the tetenal manual).

The result was better, but the problem didn't disappeared...so please, any advice regarding this problem will be greatly appreciated.

I attach an image (test copy), inverted in order to easly recongnize the problem ( upper section, sky zone), and another image, in normal form and inverted (img 071-1 / 071).

I also want to ask you some information about the rinse after the stabilizator step; i observed that the satbilizator lets a lot of dirt on the negatives, almost ruining them; the same problem appear even if we use a washing agent after the satbilizator...

So, anybody rinse after the stabilizator? How do you manage to have clean negatives?

Many thanks

[Robert Ley]

Is your Expert Drum absolutely dry when you load the film? Are you doing a pre-wash?

It looks like the negs may have gotten wet before processing or you may not be using enough chemistry. It is very hard to see what you are talking about on my monitor.

Is this something that has happened on every run or just this one run of film?

What Tetenal kit are you using? They have a Developer and Blix kit and one that has a separate bleach and fix.

I think that you need to give us as much info on your processing as possible.

I have been using Fuji Hunt C-41 chemistry with a great deal of success and no problems for the past four years.

[tgtaylor]

You rinse the film before the stablizer step not after. The stablizer contains a wetting agent which rinsing would remove and may also impare the dye stability.

Use Kodak chemistry.

Thomas

[Jan Normandale]

I have been using Fuji Hunt C-41 chemistry with a great deal of success and no problems for the past four years.

Robert, where are you sourcing the Fuji Hunt kit? I've only been able to locate the Unicolor kits

[mircea nicolae]

M Wittman and I are using:

• no prewash,
  
• 330 ml of chems / 10 sheets, as specified in the Jobo 3010 manual
  
• this happened only to this run of film, and mostly damaged the 4 portra 400, and almost not at all the 2 ektar 100 sheets
  
• we were doing hand rotation as the motor is dead (cog was unscrewed beforehand), using the unit as a tempering bath - not for the first time
  
• the tetenal kit 5 L / is a blix formula, not bleach + fix

Thank you for any advice on this.

[Robert Ley]

I really like the Fuji-Hunt C-41 and RA-4 chemistry. It is easy to mix and will keep for quite a while if stored with no air in the container. I use liter and half liter plastic water and seltzer bottles and squeeze out all the air and it will last a long time (2-3months).

My source for the chemicals is: http://www.minilab.com/index.asp

You should be able to get everything that you need from these folks.

[Bruce Watson]

]the tetenal kit 5 L / is a blix formula, not bleach + fix

As has been discussed endlessly on APUG Color: Film, Paper, and Chemistry forum, blix is not the way to go. Separate bleach and fix steps work much better. Search around and read the threads to learn more about the "why" of it.

The Photograhers' Formulary has a 1 liter c-41 kit (Kodak chemistry) with separate bleach and fix steps.

[MWitmann]

You rinse the film before the stablizer step not after. The stablizer contains a wetting agent which rinsing would remove and may also impare the dye stability.

Use Kodak chemistry.

Thomas

i know that the rinse has to be done before the stabilization, but we though that would be necessary also after it, for removing all the froth that remained on the negatives.

Only after (today) we discovered that the froth was caused by the use of the stabilizer in the CPP2 lift, and that is better to dunk the negatives in a tray of stabilizer, in order to avoid the froth caused by the tank rotation.

I panicked a bit, because i really didn't want to find out after few months that the negatives are compromised, so i stabilized them once again, this time avoiding the froth problem.

Hope that now everything will be "safe".


Returing to the main problem i want to ask you if there is so much difference between the Tetenal color kit C41 and the Kodak products. Will the separation of the bleach and fix resolve the problem?

Many thanks

[Jan Pedersen]

In addition to Formulary's kit, Freestyle sell these http://www.freestylephoto.biz/66015-...ll?cat_id=1001

I have used a few of these kit's and they produce nice and clean negatives.
Rumors are that they are Fuji chems.

[MWitmann]

In addition to Formulary's kit, Freestyle sell these http://www.freestylephoto.biz/66015-...ll?cat_id=1001

I have used a few of these kit's and they produce nice and clean negatives.
Rumors are that they are Fuji chems.

Thank you Jan