Generalized processing tips for deep tanks.

Discussion in 'B&W: Film, Paper, Chemistry' started by 2F/2F, Feb 4, 2009.

  1. 2F/2F

    2F/2F Member

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    Hello,

    I just shot over 60 rolls on a project.

    An instructor has offered to loan me her 3-gallon deep tanks and rack with a 36 roll capacity.

    I have good processing times for my films (HP5 and Delta 3200) in Nikkor hand tanks with HC developer. What changes do you all think I will need to make to these times when using the deep tanks?

    Thank you in advance.
     
    Last edited by a moderator: Feb 4, 2009
  2. analogsnob

    analogsnob Member

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    I have found over the years that if the agitation plan is the same(ie 30sec initial followed by 10 sec every minuit) in both set ups the results will be very close. I have used 5 sec every 30 also with good results but it is a little clumsy. I also routinely include 15sec drain at the end which is more necessary with the big tank to minimize carryover and to find the next tank in the dark.

    35mm hangs on the reals pretty well by 120 gave me a problem which I solved with rubber bands run over the real perpendiculare with the film.

    I also would not run the basket full of 35mm both because its heavy and I was always nervous that the amount of film would exaust the developer (my fear more than fact).

    Be sure to tap the basket firmly on the bottom of the developer tank several times because there will be lots of trapped air. I always ended my agitation cycle with a strong rap. Agitation was pulling the basket up 2/3rds of the way out of solution and return. I did not tip roll film baskets the way they always said for sheet film.

    Make sure to replenish between runs and don't turn on the lights until after the first minuit in the fix.

    Good luck!
     
  3. analogsnob

    analogsnob Member

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    I should add that if you do run the basket full or nearly so make sure you have enough chemical depth to cover the top reels especially on subsiquent runs.
     
  4. John Shriver

    John Shriver Member

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    Kodak's times for "Large Tank" (which is what the 3 gallon tanks are) are about 15% longer than for "Small Tank" (like the Nikor tanks). Well, that's for Tri-X, which is a cousin to HP5+.

    Agitation technique is much more critical with racks in large tanks. Easier to get non-uniform results.
     
  5. PHOTOTONE

    PHOTOTONE Member

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    The difference in processing times is due to different agitation routines Kodak specifies for Deep Tank processing.

    I develop sheet film in large quantities in deep tanks all the time. I have found that agitation technique needs to vary depending on the film being developed. Some film requires very little agitation to produce beautiful negatives (the old Forte 200 films, for example) while others, such as the Fomapan 200 films require almost constant agitation to avoid streaks.
    I say this with the constant that the developer remains the same.

    I always use a 4 minute water pre-soak for my b/w sheet film processing in tanks. I have a separate tank that I fill with water, and put the film hangers in (in the dark) for 4 minutes with agitation before I go into the developer. This technique has solved 99% of uneven development and streaks. I would recommend this technique also for roll-film processing in deep tanks.