farmers reducer

Discussion in 'Enlarging' started by mitch brown, Jun 23, 2006.

  1. mitch brown

    mitch brown Subscriber

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    i was reading bruce barnbaums master printing class and he talks about useing bleach on prints to lighten areas.they call it potassium fericyanide. in way beyound monochrome ralph also calles it bleach but he adds some fixer. my question is , is kodak farmers reducer what they are useing /
    mitch
     
  2. Sparky

    Sparky Member

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    no. Bleach is not a 'proportional reducer'. That is to say - it'll eat up the least dense areas first. This won't happen with Farmer's. Not as much anyway. It is an equal opportunity eater of silver.
     
  3. Sparky

    Sparky Member

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    Get Donald Qualls on this - he'd be the man with the authoritative answer!
     
  4. unregistered

    unregistered Inactive

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    They are not the same. P. Ferricyanide works as described above. Mixing fixer with it will speed up the bleach action and its not a good idea, since you usually do this after the print comes out of the fixer, and only do a quick rinse before applying, so there is actually some fix still on/in the print. you mix the P. Ferri very dilute and keep a running hose handy to wash it off as you go. It is a slow process as the bleach can get away from you and go too far all of a sudden. I always do it on a almost verticle plexi glass board and have the hose hitting just below where I am bleaching and raise it up to wash quickly if I need to.
     
  5. Ole

    Ole Moderator Staff Member Moderator

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    "Farmer's Reducer" is potassium ferricyanide with a little added sodium thiosulfate.

    There are lots of different reducers, formerly known as "proportional", "Super-proportional", and "cutting". Any photography book from before 1920 has a plethora of recipes..

    A "Cutting" reducer cuts the same amount of silver(=density) from all tones, useful for gross overexposure. "Proportional" reducers cut the same fraction of silver from all densities, and were used when the plate was overdeveloped. I very bad cases a "superproportional" reducer was used, which dissolved relatively more silver in the densest areas...

    Anyway: Farmer's reducer is a "cutting" reducer.
     
  6. RalphLambrecht

    RalphLambrecht Subscriber

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    Mitch

    Farmer's Reducer has a solution A and a solution B. Solution A is the potassium ferricyanide (and bromide if you wish), and solution B is the fixer. You can use these solution together or sequentially. The effect of A is only visible after or with B. If used together, you can see the effect right away, but the mixture is not much active after about 10 to 15 minutes. If used sequentially, you don't see what A did until using B, but it lasts almost indefinately.
     
  7. ronlamarsh

    ronlamarsh Member

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    I actually Bruces workshop and can say that his method works better "for me" (to be read"more controlable") than anything else I have tried. Bruce just mixes up about an 1/8 teaspoon of potassium ferriciynide in smoe water in a glass, it should be about medium urine yellow. Then applies it with a brush selectively keeping a hose with running water just under the area being worked on, then move up the water stream to follow the brush. After a bit of bleaching on the chosen areas with all the excess bleach rinsed off reimmerse the print in fixer for about 30sec to activate any leftover bleach pull the print inspect and rinse well then continue this cycle until you are satisfied. Caution! any fixer left in the print i.e. small patches here and there that don't get rinsed out will give you very accelerated bleaching in just that spot so like all things in the darkroom patience and process are the key.
    Secondly I have heard of another method that uses regular farmers for the whole print but it is reduced in strength about 5:1 and used on prints that have been selenium toned in selenium 20:1 which gives a very slow and controllable process(Barry Thornton " edge of darkness"). I suggest tim Rudmans toning book as it has an excellent section on bleaching. I prefer Bruces method as I rarely need to bleach that much and prefer to do it selectively. Use a good japanese caligraphy brush and try it out on some rejects first to get a feel for it. Have fun
     
  8. RalphLambrecht

    RalphLambrecht Subscriber

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    It can certainly be done this way. The two solutions will, last longer this way too. Nevertheless, it's easy to overdo it this way. The full bleaching effect is not seen until the print sees the fixer, and then it is pretty much immediate. When mixing bleach and fixer, one has a bit more control over the lightening, but the solution needs to e mixed fresh every ten minutes. Both methods work. It comes down to what you prefer, as you said.
     
  9. Jim Jones

    Jim Jones Subscriber

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    I mix a tiny bit of Potassium Ferricyanide and fixer when needed. A little goes a very long way. My 16 oz. bottle of the stuff is 20 years old, and is still nearly full. It would be better to shoot the negative so it or the print doesn't need such treatment, but I'm not that good. I AM a cheapskate, and sometimes use it to clear outdated film and paper. It has even partly salvaged a negative overexposed four or five stops due to a bad exposure meter and worse photographer.
     
  10. Markok765

    Markok765 Member

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    Can you still buy farmers reducer?
     
  11. Donald Qualls

    Donald Qualls Member

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    Actually, though Farmer's Reducer as packaged by Kodak isn't intended for proportional use, if you don't mix the solutions of the two packets it can be used that way -- as can homemade Farmer's Reducer. The difference seems to be in whether fixing of the silver converted by the ferricyanide takes place as it converts (cutting) or afterward (proportional).

    Given the prices of ferricyanide and hypo crystals, I'm not sure why anyone would buy Farmer's Reducer (especially since the components are so useful separately), but if Kodak doesn't still sell it, you can certainly get it from Photographer's Formulary.
     
  12. Jim Chinn

    Jim Chinn Member

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    Like Donald said, it is much better to buy the potassium ferricyanide in bulk. You then have the freedom to mix various dillutions (such as one for detail work and one for print imersion) and only mix the quantity needed at the time.
     
  13. Monophoto

    Monophoto Member

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    I did a workshop many years ago with George Krause, the master of chemically torturing both negatives and prints.

    George's approach bleaching prints was to mix a small batch of bleach when and as needed from potassicum ferricyanide crystals. With the print still in the fixer, he would take a small amount of fixer directly from the fixer tray in a small container (a shot glass, a one-ounce "graduate", or one of those disposable plastic condiment cups from the fast-food place), add a few crystals of pot ferri until the color was right (about the color of weak tea, or as someone said here, healthy unine). Then he would take the print out of the fixer, drain it and blow away the surface moisture, and paint the bleach onto the print using either a small brush or a cotton swab. Then he would drop the print back into the fixer to stop the bleaching action. He would repeat this process several times until he achieved the reduction that he was looking for.

    George would also bleach or intensify negatives as he felt they required that kind of torture.

    It's really interesting to watch a master printer work!
     
  14. Rob Skeoch

    Rob Skeoch Advertiser Advertiser

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    This is how I use Farmers Reducer. I buy the Kodak product and mix it in two small bottles until I need it.
    When I get a print that's too dark I slip the whole print into a tray of Reducer and lighten it up a bit. Now sometimes I get a print that the white is just too dark... like a cala lily on a black background. So what I do is, I take some cotton balls and apply the Reducer to the white area to lighten it up.
    Of course this happens too slowly for me so I get frustrated and put the whole print in the tray. Then I leave it in the tray too long and totally bleach out the white areas, ruining the print.
    Then I find the negative, reprint the photo lighter, and throw away the print that I over lightened.
    I must enjoy using it this way since I've repeated this a number of times and have become very skilled at it.
    -Rob Skeoch
     
  15. Allen Friday

    Allen Friday Member

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    Ansel Adams gives formulas for Kodak R-4a (Farmers Reducer) and for Kodak R-4b (Farmers Reducer, two-bath version) on pages 257 and 258 of "The Negative." R-4a is a "cutting" reducer, meaning it "affects the low values first" (p. 237.) R-4b is a proportional reducer and is thus recommended for reducing over-developed negatives.

    Either can be used on prints. If you are selectively bleaching small areas, R-4a is probably the way to go. The issue with prints, however, is how to control the bleaching to prevent over bleaching. The easy way to do this is to add more part b than part a, up to 4 times the amount. It slows down the bleaching effect. You want to mix uup very small amounts of the reducer, as it only lasts about 10 minutes.

    Lambrecht and Woodhouse discuss their method of selectively bleaching prints, and give a formula for "ferry" on p.218-9 of "Way Beyond Monochrome."