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  1. #11

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    [QUOTE=Photo Engineer;609198]Once Ferric EDTA is mixed with Hypo they begin to react. In fact, Hypo on its own is reacting with air and just speeds up when mixed with Ferriic EDTA. Therefore the mixture is not stable. This mixture is a weak oxidant and is not strong enough to fully bleach and fix film if mixed at the right concentrations. /QUOTE]

    I wondered about the bleach formulas based on peracid agents (see US 6703292 for example) Kodak has introduced...

  2. #12
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    Peracids work. They were devised many years ago and in fact a peracid blix was devised using a super strong silver ion complexing agent. They were not used until recently. The first bleach ever used for color film and paper was quinone + sulfuric acid.

    I should add, after getting a chance to check, that patent # appears to be incorrect. It is for making semiconductor wafers.

    PE
    Last edited by Photo Engineer; 03-31-2008 at 10:21 AM. Click to view previous post history.

  3. #13

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    Quote Originally Posted by Photo Engineer View Post
    I should add, after getting a chance to check, that patent # appears to be incorrect. It is for making semiconductor wafers.
    I am sorry. The correct # is US 6703192: Photographic peracid bleaching composition, processing kit, and method of use.

  4. #14
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    Quote Originally Posted by CRhymer View Post
    Hello Tiberius,

    You don't say what system you are using for C-41 - small tank, drum, etc. Since Kodak does not have a "home" C-41 kit any more (as far as I know) it can be a bit confusing choosing the right size and type of individual chemistry. I suspect you are using single use rather than a replenished system.
    I am using steel reels and tanks for processing 35mm and 120 color print film. I temper using a bath of water to which I add either hot or cold water to adjust the temperature. I usually run at about 101-102 F to compensate for the loss between the tub and the tank.

    I have been using a Tetenal powdered C41 kit, but that gets expensive if you process more than that quantity, which I was and sometimes do. Chemistry can last a long time if you bottle it without air.

    I ordered the kodak developer and stabalizer plus a universal blix (RA4 and C41). Since I ordered the last one in existence, I'm transitioning to kodak flexicolor chemistry entirely.

    If you are determined to use blix, B&H has Tetenal Universal Bleach/Fix http://www.bhphotovideo.com/c/produc...ch_Fix_15.html
    The advantage I got from blix was that I found a cheap product which gave two different dilutions for C41 and RA4 (I do color printing too). I've seen that myself while I was looking, but that blix there is only for films (universal meaning print and slide), so it's a no-go. I don't want to really want to experiment for this. Now that that advantage is gone, there is no reason for me to use a blix in the C41 (kodak sells the blix for RA4 which I will use because too many trays in dark can = bad news bears)

  5. #15
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    I use a WR13 safelight (actually 2 of them) and can see pretty well when I work on color paper. For film it is totally dark, of course.

    PE

  6. #16

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    Hello Tiberius,

    It sounds like you now have a handle on the rather confusing array of chemistry out there for different C-41 processors. I had also forgotten that you may be on a tight budget (but who wants to spend extra anyway?). While I use a Jobo now, I have used stainless reels and tanks in a tempered bath in the past and it works well. The Kodak chemistry with separate bleach and fix will work well for you. Ilford is distributing Paterson products now, so maybe their chemistry will become available again (IIRC that was the universal blix you had). I am in the North of Canada, so my supply situation is rather different that yours. Have you thought of doing E-6? Kodak still has a 5 litre E-6 kit, http://www.bhphotovideo.com/c/produc...rocessing.html
    although shipping could be a problem. If you can do C-41 you can do E-6. 120 transparencies will blow your socks off. Slide film may not be around all that much longer.

    Cheers,
    Clarence

  7. #17
    tiberiustibz's Avatar
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    Quote Originally Posted by Photo Engineer View Post
    I use a WR13 safelight (actually 2 of them) and can see pretty well when I work on color paper. For film it is totally dark, of course.

    PE
    I ran a test yesterday with a safelight (might have been red or red-orange) and left the paper by the enlarger for 45 seconds and then processed it. I now have a lovely cyan sheet of paper. I might try a dark amber one, but for now I'm in the dark.

    I am on a tight budget because I'm in highschool and if I run out of money I can't just decide to get a day job during the week :-(.

    E6 is just not worth it in terms of time and money. It's not that exciting because in the end you have slides (yay) but I'm not doing ilfochrome so I'm stuck with scanning and that would be traitor-esque. I just send them away in fuji mailers for now.

  8. #18
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    A red or red-orange safelight will fog the red layer and produce a cyan fog.

    The amber light was designed specifically to fit a hole in the sensitivity of the paper and allow a safelight that caused no fog.

    PE

  9. #19

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    Quote Originally Posted by tiberiustibz View Post
    ....
    E6 is just not worth it in terms of time and money. It's not that exciting because in the end you have slides (yay) but I'm not doing ilfochrome so I'm stuck with scanning and that would be traitor-esque. I just send them away in fuji mailers for now.
    The Delineascope GK is often available for about $30.00 if you can do local pick up. It projects up to lantern slide size or 4x5 cut down. B&W transparencies are pretty impressive too and not expensive to do. I think you said you were doing B&W reversal at school. Of course, if you don't like watching projected slides it is not for you.

    Cheers,
    Clarence

  10. #20
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    I'm not entirely sure that I'm holding the developer within .25 degrees. It's close, but if it's more like 1 degree am I wasting my time processing at home? I'm thinking of doing RA4 exclusively and skip the C41 to save on the $$$ for small volumes... Then again if I start shooting 4x5 I will continue processing. Good processing (better job than I do) gets more expensive than CVS.

    If i'm off by a degree am I screwed? My prints are looking great and if that's the determining factor I'm AOK. Color accuracy isn't an issue. I'm not shooting color charts.

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