Capacity of Flexicolor chemicals (C-41)

[Atlantis]

I have some questions about the capacity of C-41 Kodak Flexicolor chemicals. This is the first time I buy these chemicals and process C-41, so I want to be sure about it. I use a 600 ml Paterson tank which can process two rolls.

Feel free to answer any of the questions.

CAPACITY

1) Bleach, Fixer, Final Rinse: How many times can they be used? A Kodak paper says that a quart/liter of any of them can be used for ten 35mm rolls. Is it like this or do you use them more times? Do I have to add time to Bleach and Fixer processes every time I develop or it is not necessary?

2) Is there for Flexicolor Fixer a test like the one used in B&W fixer, calculating the double of the clearing time? What calculation must be done?

3) Kodak says in its Flexicolor paper that solutions of Bleach, Fixer and FR must be used for no longer than 8 weeks once prepared. I mixed a bottle of fixer like 7 months ago (half fixer, half water). Should I discard the mix by now? (Yesterday I used it, without knowing this, and it seemed to work fine, but I don't know how much longer I could use it.)

4) So far, I have been using the Final Rinse one-shot, just like I do with Photoflo in B&W. But apparently it could be used more times. Should I prepare one liter and use it for 10 rolls?

USE AFTER EXPIRATION DATE

5) How longer can each of the four chemicals be used after the expiration date indicated in the bottle?

In my case, the Bleach I am using has already expired. The Fixer expires this month, 11/17, and I still have a lot and I don’t shoot too frequently. The Developer and FR expire by mid-2018.

 

[x-ray]

You're going to get a lot of answers telling you to use them beyond their expiration and capacity. It really depends on how critical you are and how much you care about your images. Consider this, who knows more about Kodak chemicals, Kodak the company that invented the process or people on a forum that just guess. The way to get the best quality and consistent results is to follow the experts recommendations. On the other hand if you can't tell the difference or don't care then it doesn't matter.

 

[aizan]

everything you need to know (especially page 3):

http://125px.com/docs/chemicals/kodak/cis211-Flexicolor_in_small_tank.pdf

 

[x-ray]

Here's an article by two guys that really know their stuff about C-41. I believe the 2nd person was an engineer for Koday and the first may have worked with them too but again not sure. In any case there's a huge amount of information regarding why you need to observe capacity and age recommendations by Kodak. Also they go into the need for your bleach to be well oxidized. These are things my Kodak TSR taught me many years ago and I've never ruined a tool or sheet in several thousand that I've processed.

https://www.photo.net/discuss/threads/correcting-leuco-cyan-dye-in-developed-c41-film.246608/

Take a read.

It really comes down to whether you know correct color when you see it and whether you care what your images look like. A lot of people are just happy to get something that resembles color whether correct or not.

 

[Atlantis]

Thank you, X-ray and Aizan.

The article that Aizan linked was the one I read, that is why I mentioned the same information. I am not someone who likes taking risks with my films, or doesn’t care about the quality of processing. But in my short experience I learned that, for example, Photoflo lasts much longer, years more, than what is indicated. Mixed D-76, if well kept, could last longer than the 6 months recommended by Kodak. I even read that the expiration date of bleach was not something to take too seriously, though I don't know how much longer you can use it. And so on...

So basically I am looking for real experiences. I wasn't able to find info about Flexicolor chemicals, that is why I asked.

Aizan and X-ray, do you use these Kodak C-41 chemicals?

X-ray, how do you oxidize bleach?

 

[x-ray]

I ran a lot of C41 in years past. I was over the photo, TV and motion picture department for a good size ad agency then opened my own studio with a lab thirty five years ago.

We mixed 5 gal quantities of C41 and used an aquarium air pump with diffuser. We just submerged the diffuser and turned the pump on and let it run contineous. We monitored our process closely and never had an issue.

Oxidation in the developer is something of concern. My degree is in chemistry and oxidation not only occurs when air contacts the developer it's a byproduct of the development process. Every roll you run oxidizes the developer. It's a reduction / oxidation process. The silver halide emulsion is reduced to metallic silver proportionate to the amount of light that's struck it and in return the developing agent is oxidized. This REDOX reaction occurs whether oxygen is present or not. Oxidation depletes the developers ability to reduce silver halide.

There is a safety margin built in but it takes into account aerial oxidation. I personally trust the recommendations. In a professional environment a lab can't risk the loss of someone's work. In my studio I couldn't risk not delivering a perfect product. Again it goes back to how much you want to risk your film and how critical you are.

I've run many thousands of rolls of E6,E4,E3, C22 and C41 and always followed the recommendations and over fifty years never had a problem caused by carelessness.

 

[x-ray]

One more comment, it's not only oxidation of the developer that's an issue, other byproducts such as bromide builds up in the developer and other compounds are depleted. Replenishment is one way around this using the correct replenisher not working strength developer. Developer is different chemically than replenisher. And again oxidation is critical in the bleach. Specific gravity and PH are other things that need to be monitored if you want to exceed capacities and life or replenish your chemicals.

 

[Corran]

Most folks nowadays are printing color scans digitally and shooting film for personal work and not for large-scale commercial projects. As such, personally I buy 5L kits and mix up 2.5L batches and use them for 3-4 months, usually way past capacity. Any slight color shift is easily corrected in the scan on C-41 since you've got to invert and tweak the color anyway, so there's no problem...I have more issues with expired film with gross crossover than chemical issues, so I generally don't shoot really old C-41.

Generally though I would definitely suggest bleaching for longer than indicated, and continue to add time throughout usage. Since I do both C-41 and E-6, I share the bleach between them and change it out twice as often. Works fine.

If I was shooting 100 rolls of a single batch in a studio for paid clients of course I would not be cavalier about it - if you are doing that then perhaps be a bit more careful or send it to a lab.

 

[SaveKodak]

You can use Final Rinse more times but it's so cheap, why bother? I use 65% used fix and 35% fresh, and 88% used bleach to 12% fresh. The used bleach is aerated with an aquarium pump for 2 hours every day. Many people use the fixer one-shot simply because it's extremely cheap. I really only replenish fix to reduce the # of times I have to go to a chemical disposal facility.

Many people do use the bleach well beyond these rates, but I want to keep everything within recommendations. BTW I use a Phototherm which is why I'm so specific about the percentages.

Edit: Oh and just to clarify. I use 5L jugs. When the used jug becomes full, I discard 4L from it. Bleach goes down the drain, fix goes into a storage container until that's full. Then it goes to a chemical disposal facility.

 

[Atlantis]

The developer, which is the most important, I use it fresh and one-shot. When I expose 2 rolls, I prepare 600ml of developer with three different syringes (for parts A, B and C). And I think I am going to end it before its “expiration date”.

Corran, SaveKodak, X-ray, so basically you use bleach, fixer and FR, like 10 rolls per liter? Do you use Kodak Flexicolor or another brand?

Corran, when you get color shifts, is it because you use mixed developer beyond its maximum storage time? (in the case of Flexicolor developer, that would be 6 weeks). Do you know what happens to the film if it is processed with outdated bleach or fixer? For example, when color film is not properly fixed, you see it milky, like in B&W?

An aquarium pump for 2 hours every day? Really? Give me a break… But if I don’t do this, I suppose I can do at least the 10 rolls recommended... I mean, the oxidation is just for extending the capacity, right?

 

[x-ray]

I've run Kodak c-41 in my commercial studio lab. Not as much as E6 but a considerable abount.

Read this.

https://www.photo.net/discuss/threads/correcting-leuco-cyan-dye-in-developed-c41-film.246608/

The two guys discussing this know their stuff. I believe both were with Kodak.

Without adequate oxidation of the bleach you'll form leuco cyan dyes creating crossover issues that can't easily be corrected. As to whether you recognize youve got a problem I can't say. I see a lot of images on the internet that have terrible crossover and are poorly exposed and scanned and people are proud of them and the get rave comments. so not everyone's standards are the same and just producing a color image is good enough.

Edit: no the oxidation is important from the first roll onward. Not oxidizing, you take a chance. Every professional lab and my own studio lab aerate. I aerated from the time I mixed the bleach. I'll say in severally thousand rolls and sheets I never had an issue.

Kodaks recomendations are there for reason. The in enter C-41 and know how to get optimum results better than anyone else. They are the experts.