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  1. #1
    olleorama's Avatar
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    C41 for RA4 papers?

    I know that RA4 chemistry can be used for film, but can C41 be used for papers?

  2. #2
    Greg Davis's Avatar
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    No, get RA-4 chemicals. They are much cheaper than C-41, too.
    www.gregorytdavis.com

    Did millions of people suddenly disappear? This may have an answer.

    "No one knows that day or hour, not even the angels in heaven, nor the Son, but only the Father." -Matthew 24:36

  3. #3
    David Lyga's Avatar
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    RA-4 all the way: I do the following: with Kodak dev/repl RT (roller transport) I mix as specified, then dilute that 1 + 4. I process paper at ambient (80F) for 2 - 3 minutes. I develop color film (at 105F) from 12 minutes (for ISO 100) to 16 minutes (ISO 800). I store the chems (either diluted or not) in clear, plastic soda/juice bottles) and if filled to the very brim, never expire (despite what admonishment might transpire with that statement). It works for me and will work for anyone. That is the most hassle free way to process color. Everything I do is 'one shot'. Color dev is very capable of such dilution and what 'fails' first is not the exhaustion of the developer but, rather, the presence of bromide that the film gives off. With color development a tiny bit of bromide slows things down tremendously, unlike with the more attenuated effect with BW process.

    Also, I do not use or buy the BLIX. I use regular or even more diluted stop bath, then fix, then use a solution of potassium ferricyanide for the film (1 gram per 20ml water). That clears the film nicely in about two minutes and you need only enough to evenly coat the film (just use wetting agent); as this bleaching is a process 'to finality' you do not have to worry about unevenness. (NOTE: if you want slightly more contrast omit the bleach, as the color coupler plus the silver already there will add to the contrast.) Then a brief fix again (same fix) for about 30 seconds, then wash and dry. For paper, similarly, I stop and fix, then into a potassium bromide bath (this time far less potent than for films: only 1 gram potassium ferricyanide in 100ml water. That for about 1 minute, then, again fix (same fix) for about 10 seconds. Wash and dry.

    I cannot come up with a more economical way to do this. The ONLY 'color' chemical involved is the dev/repl RT because the potassium ferricyanide is also a BW chemical. I buy from pdisupply.com in Rochester, NY.
    Last edited by David Lyga; 07-30-2011 at 11:46 AM. Click to view previous post history.

  4. #4
    Photo Engineer's Avatar
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    I now know that no one cares about accurate dye hues or good image stability by the way you want to abuse your film and paper during processing. You may as well do things digitally.

    If you wonder why I say this, see my other posts on similar or identical topics.

    PE

  5. #5
    David Lyga's Avatar
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    I confess that I am not up to the scientific parameters that PE is. But, what I said 'works' and could well be a nontheoretical 'solution' to the solution problem for people who shun utter scientific precision in favor of a simpler 'pragmatism'.

    I fully respect PE's caveat and am actually happy he muddied the water, because my 'science' is certainly not pure. But, in the real world, sometimes 'really good enough' is good enough. I have held prints done like this for a decade or more and they still look good, if not excellent. My ego is not worth defending (is anyone's?) over 'my way' but my post was simply meant to provide an easier approach than strict science dictates and mandates. We learned to tolerate utter garbage from phamacy 'one hour' stops (most of the time due to unexposure by flashes that were 'sold' by stating that they were more powerful than they actually were); this method that I have proposed is much, much better than that. But, it must be admitted that PE really is the authority here (and I say that with truth and respect). I do not have all (if any?) of the true answers and I welcome both sides of the argument. Both sides are needed. Few here might really care about the last amount of precision and, with many years of experience that we (or most?) possess with the color process, how many really believe, today, that the earth would come to an end (as at least I once did) if we dare to let the temperature deviate so much as 1/2 degree from the designated 'rule'.

    This forum is not definitive, but, instead, evolving and dynamic. Clarification and augmentation are essential ingredients for us to all grow, both intellectually and pragmatically. In this round-about way both of us are 'correct' (but I would slant my life's worth on PE's more theoretical approach in order to cover every last possibility.) My way is 'easier access'. - David Lyga.
    Last edited by David Lyga; 07-30-2011 at 12:30 PM. Click to view previous post history.

  6. #6
    Greg Davis's Avatar
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    Holy crap! And then you wonder why you don't get clean whites and other problems? If you aren't even going to try using the right process and the proper instructions for them, maybe you shouldn't be advising other people when they are trying to learn.
    www.gregorytdavis.com

    Did millions of people suddenly disappear? This may have an answer.

    "No one knows that day or hour, not even the angels in heaven, nor the Son, but only the Father." -Matthew 24:36

  7. #7
    RPC
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    Quote Originally Posted by olleorama View Post
    I know that RA4 chemistry can be used for film...
    Please be careful with what you say. This is only partially true and may mislead the unwary. Yes, RA-4 can develop film and C-41 can develop paper but you won't get proper results.

    RPC

  8. #8
    David Lyga's Avatar
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    Hold on, Mr "Holy Crap" Davis, the pure whites don't show forth even with 'proper' development and blix. My way has NOTHING (and I have tested) to do with the purity of the white base. (But it was fun to thrash me, right?) - David Lyga.
    Last edited by David Lyga; 07-31-2011 at 11:17 AM. Click to view previous post history.

  9. #9
    Greg Davis's Avatar
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    I'm in the process of moving for the next few weeks, when I am done and settled, I will shoot two sheets of color negative film and process one in standard C-41 and the other with your process, then I will print each negative with the standard RA-4 and with your process. I'll post the results here and we will see how it compares directly.
    www.gregorytdavis.com

    Did millions of people suddenly disappear? This may have an answer.

    "No one knows that day or hour, not even the angels in heaven, nor the Son, but only the Father." -Matthew 24:36

  10. #10
    olleorama's Avatar
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    The reason I asked was because I wanted to know. Just curious.

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