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  1. #1

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    Does oxidized RA-4 chemistry grey-down whites?

    The subject line sums up the question.

    I mixed up a gallon Kodak Ektacolor RA kit about a week ago and when I used the last bit of it yesterday, the developer was quite a bit darker out of the bottle and the white borders of the prints were definitely "dingy." I assume this is an oxidation effect? If so, is it primarily oxidation of the developer or the bleach that's causing it?

    Other than the above problem, I have to say my first RA-4 printing experience has been pretty painless. It took a couple sessions to get a handle on filtration, but once I realized the one wheel was the "Christmas Wheel" (green/red) and the other the "Easter Wheel" (blue/yellow) I was in business. By yesterday's session I could pretty much settle on the right filter pack with 3 test strips.

  2. #2

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    Bleach keeps a lot longer then developer. When I make up chemicals I make up a double batch of bleach. Even with the bleach hanging around 2x the time of the developer I don't think I've ever seen the bleach fail. Bleach actually needs oxygen for C-41 and I guess for RA-4 to.

  3. #3
    Bob Carnie's Avatar
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    Hi Poco

    I did not forget about you, I made the ring around and when I can break loose to take some pics and organize the chart I will send it to this thread as an attachment, give me about a week .
    Now , your christmas wheel is actually green/magenta and if you move both wheels equally in either direction they are your red / green.
    Also if you move all three at the same time you will turn the lights brighter or darker .
    You will find very few occasions where you need the third wheel ( cross processed or poorly processed negatives or if you want to introduce nuetral density for some reason.)
    I agree with Nick, but we have found here that the bleach can suddenly go and it is a remix.
    Hope you are having fun.
    best regards
    Bob

  4. #4

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    Thanks for the replies, guys. Sounds like the developer is the problem.

    I was mostly joking about the christmas-easter thing and realize there are lots of subtleties in finding the right filter pack which I still haven't grasped. A few darkroom sessions has hardly made me a competent color printer, but I am pleased by the half-way rational color rendition I can now quite easily get.

    Bob, I've read that dialing in "C" only adds density as you say. Would the results be in any way different from just decreasing exposure time?

  5. #5
    Ed Sukach's Avatar
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    Oxidized Color developer usually will have the effect of not producing a decent "Black". The remaining colors will degrade as well, but the "graying" of that which should be black is most noticeable.

    That said, If the mixed color developer is decidedly "dark" it is most probably, shot.

    Be careful of Color Developer "carry-over" into the Bleach-Fix. That is why shortstop is necessary in RA-4 processing.
    Carpe erratum!!

    Ed Sukach, FFP.

  6. #6
    Bob Carnie's Avatar
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    Hi Poco

    the c dial is actually for cyan / red. it rarley gets used in RA4 printing, What I meant was if you use all three filters at once all that will happen is the third filter value will be the amount of nuetral density you have added to the printing pack which will darken if you add and lighten if you take away

    30yellow, 50 magenta and 10 cyan

    this pack will give you 10 units of nuetral density or approx 1/3 stop
    take away the 10 cyan and you will lighten the print by 1/3 stop
    ( I cannot think of any practical situation where you would want to do this)
    in most ra4 printing you will only use the yellow and magenta filter

    When I print cibachrome I have found quite often I need to use the cyan filter

    0 yellow , 20 magenta and 10 cyan- cibachrome balance(new universal paper)

    When I print cross process negatives I also have found I have needed to use the cyan filter

    120 yellow, 0 magenta and 30 cyan - cross process RA4 balance

    Just so you are aware you should always be only using two of the filters at any given time for colour printing.
    I hope this helps

  7. #7

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    RA 4 Developer should last more than a week.

  8. #8

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    To clarify, I don't believe the developer went bad within a week. My blacks were still fine and I noticed no real difference in color rendition with the last batch I used. But there was a definite shift in the white border of the prints. The whites had lost their snap compared to prints I made with the freshly mixed chemistry. I seriously doubt it's a contamination issue either, but who knows.

    Well, I'll keep fooling with the stuff and see how it goes.

    Thanks, everyone, for your thoughts.

    -Michael

  9. #9
    Bob Carnie's Avatar
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    Poco

    Do you have a radio, humidifyer or any device with led lights, you may be getting a slight fog which is creating this density, If it is cyan looking a red Led can be the culprit. you will not see this shift in the midtones or blacks.

  10. #10

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    Yes, fogging is something I'm going to have to test for.

    Thanks, Bob.

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