Help! c-41 in a jobo

[frotog]

I have a cpp-2 and I'm thinking of running flexicolor c-41 for the first time. I'd like to be able to process 35mm to 5x7 sheet film w/ results comparable to my pro lab in nyc. Poor material handling and heavy fedex bills have inspired my decision to attempt untethering myself from my lab. I have a few questions before I head out into the spooky world of diy c-41...
1. Is my jobo cpp-2 up to the task or would I be better off hunting down a used atl?
2. Should I be concerned about accurately hitting the 3:30 normal development times? How do I compensate for the time it takes to introduce the chem. through the lift as well as the time it takes to dump chem. out?
3. What's the best speed setting to use?

 

[Photo Engineer]

The Jobo processor is all I use and does an excellent job with C41. The problem is that the 2000 series drums will safely handle only 4x5 film on the reels. You need a 3000 series drum for sizes of film 4x5 and larger.

And, you have to have a Jobo that will take the 3000 series drums.

PE

 

[frotog]

I have the 3006 series drum. Using it in the past w/ long b/w development times (long in comparison to c-41!) I never worried too much about the approx. 30 seconds it takes to pour chem. into drum nor the 30" it takes to drain the chemistry. How do you factor this into the short c-41 development time? I can see starting the development time as soon as you begin pouring the developer into the lift. But should I then wait until the 3'30" has elapsed before I drain the developer? Or should I start the draining at 3' and attempt the beginning of the bleach cycle right at 3'30"? It seems to me that if I use the former technique I'll end up overdeveloping and the latter, underdeveloping. With 15% - 20% of the overall development time devoted to loading and dumping chemistry how is it possible to hit the target time of 3'30"? The prospect of trying to do pull development makes my head spin even faster.

 

[Lopaka]

I have had good success with processing C-41 in my CPP-2. Normally, drain time is part of the development time. I have only done film on reels, though and my drain time is no more than 15 seconds. I suggest you run some tests and see how it works for you. Most important is to be consistent with temperature. I run the drum with film loaded in a dry tempering step for 5 minutes before introducing the chemistry to make sure film, reels and drum are up to processing temp, otherwise it will pull down the developer temp as it is loaded.

Bob

 

[Lopaka]

Speed settings - the higher speed settings (approx 80 rpm) are recommended for the 1500 and 2500 series drums and the lower settings ( approx 40-50 rpm) for the 3000 series drums.

Bob

 

[Mick Fagan]

I've been doing C41 for years, with a lift.

Using 500ml of solution, it takes about 10 seconds to drain.

I lift the lift, at 3'15", drain, which takes 10 seconds, drop the lift (gently) then immediately start to load the next solution.

By the time I'm loading the second solution, it is 3'30".

The main thing is to work out a system and stick to the same procedure every time. Consistency is what you require.

Mick.

 

[frotog]

Thanks to everyone who responded. As a first-time apug user I'm extremely impressed w/ this forum! I'm heading into the drkrm. to experiment tomorrow. As far as the speed setting goes...does everyone agree w/ Lopaka's recommendations? Are there any advantages/disadvantages to using more or less agitation? Are Lopaka's #'s Jobo's recommendations?

 

[glbeas]

I agree on geometric terms about the rotation speed. The unit will rotate a big drum the same RPM as a small one, but with a larger circumference you will be moving developer across the film at a higher rate. A slower rotation speed with the larger drum approximates the peripheral speed of a small drum at the higher rotation speed.

 

[Ed Sukach]

I have a cpp-2 and I'm thinking of running flexicolor c-41 for the first time. I'd like to be able to process 35mm to 5x7 sheet film w/ results comparable to my pro lab in nyc. Poor material handling and heavy fedex bills have inspired my decision to attempt untethering myself from my lab. I have a few questions before I head out into the spooky world of diy c-41...
1. Is my jobo cpp-2 up to the task or would I be better off hunting down a used atl?

Yes, the CPP-2 is adequate. I've been doing that since 1993 - with 35mm and 120. With one-shot chemistry, I can obtain better results than the "best" commercial labs I've used.
I'll have to check --- WILL an ATL do 4 x 5 - or 5 x 7?

2. Should I be concerned about accurately hitting the 3:30 normal development times?

I'm not. I've made a few errors over the years, and other than misloading the tanks (once I did pour fixer in first ..) I've lost *very* little film. BTW ... are you sure the Flexicolor time at 38C is 3 minutes, 30 seconds? I've never used Flexiclor, but all of the rest specifed 3 minutes, 15 seconds.

How do I compensate for the time it takes to introduce the chem. through the lift as well as the time it takes to dump chem. out?

I don't even try. I may be fast but it only takes 8 or 10 seconds to pour the chemistry in; and an equal time to dump it. I think the pouring in and dumping out compensate for each other.

3. What's the best speed setting to use?

I have an older CPP-2 and the rotation speed is set at "P" - for C-41, E-6, RA-4 and all black and white film and paper. 4" x 5" may be different - do you have a copy of the manual?

 

[frotog]

Thanks for your response Ed. No, I do not have a copy of the manual. Nor do I have any of those legendary issues of the rotary processing journal. And you are right about developer time in flexicolor chem. for N dev. being 3:15. I wonder how much difference in results one gets processing sheet film in expert drums at the "p" setting versus higher rpm's. I guess c-41 is like b/w in this regard - one can accomplish push/pull variations from N dev. by increasing or decreasing rotation speed right? Or does it make more sense to adjust the development time?

 

[hka]

I guess c-41 is like b/w in this regard - one can accomplish push/pull variations from N dev. by increasing or decreasing rotation speed right? Or does it make more sense to adjust the development time?

I think that adjusting time en temperature make more sense than speed. In my case I set the temp.at 36,5C and time @ 3:15 for Fuji en 3:30 for Kodak films.

 

[Ed Sukach]

... No, I do not have a copy of the manual...

Here I go again. PM your address and I'll send you a copy.

I guess c-41 is like b/w in this regard - one can accomplish push/pull variations from N dev. by increasing or decreasing rotation speed right? Or does it make more sense to adjust the development time?

I think that the relation of rotation speed to development time would be a nebulous one, at best. To tell the truth, this is the first time I've heard of "fine" (or gross) tuning by altering rotation speed. I'd be interested - somewhat ... can you cite a source?

For me - I'd use time.