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  1. #51

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    Quote Originally Posted by RalphLambrecht View Post
    first oall, consider this a cosmetic flaw. it's what's left of the antihalation layer of the film and has no negative effect on picture quality.
    SInce it's purple, hence close to magenta, does it affect the paper grade needed?

  2. #52
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    Quote Originally Posted by mwdake View Post
    Be careful, as others have already pointed out you should try to keep all chemicals and washes within a few degrees of each other.
    This is true for Efke and some other "non-Modern" film stock. HOWEVER, modern films from Kodak, Ilford and Fuji are all quite robust. There is really no need to control the temp of the B&W chemistry this closely anymore. Stop, fix, HCA and wash can be anywhere above 20 degrees C or so and below 30 degrees C.

  3. #53

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    This is true for Efke and some other "non-Modern" film stock. HOWEVER, modern films from Kodak, Ilford and Fuji are all quite robust. There is really no need to control the temp of the B&W chemistry this closely anymore. Stop, fix, HCA and wash can be anywhere above 20 degrees C or so and below 30 degrees C.
    True, but he was not below 30 C.
    I understand warm water is not so bad but going from 18 to 30 may not be so good and it is a slippery slope as maybe next time the OP uses 33 or 35.
    I don't think there are many places where the cold tap water comes out at 30 C so maybe he is heating the water or using a mix of hot and cold taps so it would be easy to make a mistake and gte it much hotter.

    I live in a warm climates where the cold water comes out at 27 in the summer and 25 in the winter. I wash all the time in that water but I never heat the wash water or use a combination of hot and cold taps.

  4. #54
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    The danger of large temperature swings is that the film may reticulate, ie the emulsion splits into lots of crazy patterns.

  5. #55

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    No major film manufacturer recommends a presoak. the emulsion is made to absorb developer evenly and the presoak defeats this.

    The key to getting rid of purple antihalation dye is fresh fix, read never used, and over agitate it. It is a process that goes to completion unlike developer so nothing is hurt. Then wash and stand soak as required. Purple will give some contrast increase with VC paper, so unless you can control it, results will be variable. You can not substitute more wash for non fresh fix.

  6. #56
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    Quote Originally Posted by Ronald Moravec View Post
    No major film manufacturer recommends a presoak. the emulsion is made to absorb developer evenly and the presoak defeats this.

    The key to getting rid of purple antihalation dye is fresh fix, read never used, and over agitate it. It is a process that goes to completion unlike developer so nothing is hurt. Then wash and stand soak as required. Purple will give some contrast increase with VC paper, so unless you can control it, results will be variable. You can not substitute more wash for non fresh fix.
    this definitely works for metwo-bath fixingand a good wash = no purple
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  7. #57

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    Quote Originally Posted by Ronald Moravec View Post
    No major film manufacturer recommends a presoak. the emulsion is made to absorb developer evenly and the presoak defeats this.
    Can you give evidence of this? I'd have expected to see a lot more moans and groans from the pre-soakers and a total rejection of the practice by now if what you say followed inevitably. While no major film manufacturer may recommend a pre-soak( I presume you mean Ilford, Kodak and Fuji) I haven't seen any one of them telling us that a pre-soak actually prevents the absorption of developer evenly.

    My recollection of what Simon Galley said was that in Ilford's opinion a pre-soak was unnecessary but not that it actually did harm.


    However if there is incontrovertible evidence of the effect you state then I am happy to study it

    pentaxuser

  8. #58
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    A presoak won't help here, but it won't hurt anything either. pentaxuser is right about Simon Galley's comments - prewashing is completely unnecessary for Ilford films but no harm to it. Some eastern european manufacturers DID recommend a pre-soak, and soaking can help with evenness of developer uptake when processing prints for example, and it can be used to slightly extend development times if they're problematically short. It also prevent spots on the film if your drum wasn't totally dry - prewashing makes everything uniformly wet. If you develop colour though, prewashing becomes important for temperature control.

    You don't need 2-bath fixing for film, you just need to fix long enough. 2-bath is a technique developed to minimise time-in-fixer when fixing FB paper and therefore minimise fixer uptake into the paper.

    You can fix for too long - see the graphs in Ralph's book (WBM2). However, it takes 10+ minutes in non-hardening rapid fixer to cause measurable (not necessarily visible) damage to the silver image, and you can certainly fix to completion in less time than that. 5 minutes rapid fixer should be plenty for Tri-X, then you wash. Fixing longer (as long as you're fixing long enough for the type of fixer you're using) isn't any better than washing longer for removing the purple dye - it's just another bath into which the dye can diffuse out of the film.

  9. #59

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    Not all film bases are completely neutral and usable for reversal processing.

    If it is just the pink dye it will fade... and should not annoy RC printing unless you don't test strip.

    If it is a yellow stain then you need to refix.

    If your faucet temp is 27 use a temper bath at 27 and wash at 27 thermal shock is to be avoided.

    A presoak is unnecessary waste of water don't waste water unless you know where planet B is.

  10. #60

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    Quote Originally Posted by Xmas View Post

    A presoak is unnecessary waste of water don't waste water unless you know where planet B is.
    Unlike energy containing substances, water is not destroyed by it's use. Water goes down the drain or into the air and is reclaimed for reuse. Water is naturally purified by evaporation as well as various man operated techniques. Water conservation is only an issue if you are located in an area where fresh water is scarce.

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