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  1. #21
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    Quote Originally Posted by Bob Carnie View Post
    Thats a good question Ron,
    I wondered about that too.
    When mixing fresh chems we use a starter basically to cool down the development , ie not running to agressively.* I know this is non tech talk but bear with me. Therefore the thinking is that using one shot chemicals is basically like preparing a working tank each and every time.
    I would love not to use the starter and would appreciate your thoughts/comments on using a starter for one shot C41 developing.
    Bob
    Bob;

    The Kodak part # I gave makes 1 gallon (3.8 L) of developer that seems to exactly match the local shops process, but I don't use starter and AFAIK he does. This question of starter, no starter keeps coming up. The formulas as we mix them and devise them in research do not use a starter and are designed to match the seasoned process. So, I'm not sure what the starter is designed to do except that the developer replenisher is more concentrated with developing agent and halide salts and the starter essentially dilutes that. I would say try to avoid a developer that requires a starter.

    As far as final rinse goes, IDK what Fuji suggests, but Kodak uses a dye and coupler stabilzer and a fungicide in their final rinse. B&W films contain silver which is a good fungicide, but color contains things that fungi seem to love. So, the idea of a final rinse is logical to me.

    Since the Kodak product is proprietary, I would guess that Fuji has some sort of equivalent mix.

    PE

  2. #22

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    Quote Originally Posted by Bob Carnie View Post
    Nick
    My only problem with a replenished line is the chemical overflow from one to another and the affect of volumes of film on any chemical. I prefer the one shot mixture for the previous reasons and my percieved thoughts of byproducts of development screwing up the subsequent chemicals.

    I don't know if I got the idea from a Kodak document or somebody else but my process is basically

    Developer

    Stop

    Wash

    Bleach

    Wash

    Fix

    Wash

    Stabilizer.

    It's longer but it replaces the squeegies a machine would use with wash steps. The worry is the water carry over dilutes the next step. :o Always some thing -)

  3. #23
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    Ron
    I just got off the phone with my tech rep, regarding why starter.
    Fuji only sell replenishers for dev and bleach, the starter is to make a working tank solution.
    It is not good to run replenishers only as it would be to *active*
    He says that consider one shot as making a working tank solution each time.
    Therefore folks use the starter if you are doing a one shot method, If you are replenishing the chemicals as Nick is then you need the starter for your first mix and then replenish as needed.
    Once the 1litre combination is established its just a matter of staying within a 3-6% mixing tolerance, all things considered, temp time, He also says the agitation in the rotary processors have the most effect.
    Further he said 95% of all development is finished in the first 25seconds and the rest is tailoring.
    Pushing the time can add some *percieved* dmax , but too much push will not be good. I am thinking 1 stop max.

  4. #24
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    Thanks Bob.

    Apparently, Kodak makes a working strength developer kit that does not require starter as well as a kit that requires starter.

    To be absolutely clear, the part number that I gave is for the Kodak product that does not require starter for use in the Jobo.

    PE

  5. #25
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    Don Bryant

  6. #26
    Dug
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    Can anyone comment on using the different Kodak products in a Jobo?

    Specifically, I picked up some Kodak C-41 SM developer (175-6337) that you can mix up in 2L batches. Can I substitute this developer and use the other standard Flexicolor chemicals? (I do one-shot processing) According to the data sheet the C-41 SM developer time is 3:15 (same as the others).

    I also have C-41 RA Fixer/Replenisher (162-6571). It is for a rapid C-41 process. Can I use this fixer in a "regular" one-shot C-41 process in a Jobo? I do 4 rolls/500ml batches.

    Kodak warns against doing such naughtiness, but I am between the capacity of 1 liter kits and the larger sizes and got these items from Rainier Photographic, who closed their doors for good last Saturday.

    I plan on trying it on test rolls and will publish my findings.

  7. #27
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    Sorry Dug,, I can't help you on this.

  8. #28
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    The bleach and fix of any C-41 can be mixed with any C-41 as long as the times are appropriately adjusted based on the particular instructions. Washes may have to be adjusted accordingly as well.

    You can even omit the starter in the bleach and fix and see little problem but you may have to adjust time upwards a bit. You can go overtime in the bleach and fix with no harm as they go to completion. You may have to adjust wash times upwards to compensate.

    The restrictions on stabilzers or final rinse that I posed earlier apply as well, particulary as regarding film age (generation).

    The final wash before the stabilzer or final rinse must never be colored, nor carry colored material into the final rinse or stabilzer. If it does, image stability will suffer in some way or another. The final solution should never take on a pink or red or brown color.

    You must never wash after the stabilzer or final rinse!

    The color developer should work as advertized as long as mixing instructions and use of starter or no starter as recommended for your kit are adhered to. I never heard of the developer that you referred to, but it should work with no problem.

    Current chemical preparations for Kodak are now done by another company, but using Kodak facilities in Rochester. This was posted earlier on APUG.

    PE

  9. #29
    Dug
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    Thank you PE - Your guidelines are very helpful for us to understand some of the engineering behind these products and procedures

    The C-41 SM developer looks to be a simple repackage of standard developer chemistry to further simplify the process of preparing chemistry for smaller commercial machines. I will mix as instructed and develop for the standard 3:15 @ 38 deg C.

    The C-41 RA fix/replenish is a little confusing: RA stands for "Rapid" and it is supposed to be used for a shorter period of time with no wash required. (I don't know why one would place "RA" in the middle of the name of a C-41 process!) I plan on using it for the standard 6:30 @ 38 deg C. If fix is one of the processes that goes to completion it should be OK at a standard instead of "Rapid" time. I will follow with a final rinse.

    I'll let you all know how it goes.

    Doug

  10. #30
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    I'm familiar with the RA fix and AAMOF worked on an RA BLIX for C41 in the 60s before the process came out. If you want archival prints, you must wash after the C-41 RA fix, and this fix is more critical for time as it will increase swell and soften film. You must also use a final rinse.

    This was intended for machines with no wash or low wash rates and disposable negatives (the customer gets only digital images on CD). With no wash following the fix, the images are not all that stable IMHO.

    PE

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