Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 68,698   Posts: 1,482,557   Online: 905
      
Page 3 of 3 FirstFirst 123
Results 21 to 28 of 28
  1. #21

    Join Date
    Jan 2007
    Location
    third stone from the sun
    Shooter
    Large Format
    Posts
    717
    Quote Originally Posted by nick mulder View Post
    Ok - whew, depending on the drum that's a lot of distilled water :o - the room I load film in isn't of the wet variety unfortunately ...

    Reverse engineering your solution doesn't give me any clues as to the action of the issue itself though - ok, so now the film is wet, but how much or less 'wet' than an initial pre-wet via the usual method of less un-distilled water and a bit of agitation ... (?)
    .
    The technique of loading the film into a jobo already filled with the water/sodium metaborate prewash has been passed on here and on other forums. It seemed odd to me that this would solve the problem but then I tried it and it worked. One would have to deduce that in loading the film dry the prewash doesn't fully saturate that part of the sheet that's pressed up against the ridge of the jobo's cylinder and discrete areas of greater or lesser stain ensue. But your problem might just be the result of excessive oxidation. If the prewash technique seems like a PITA (and it is) why not first rule out oxidation by either displacing oxygen with gas or use more solution and a cork. Good luck - it took me a long time to rid my process of the gremlins you've encountered.

  2. #22
    outwest's Avatar
    Join Date
    Aug 2005
    Shooter
    Multi Format
    Posts
    312
    Images
    3
    The addition of the EDTA solution to PMK that Gordon recommends eliminates the oxidation problem. Probably not that anyway, as the worst blotching I had was with MaxPyro. I think it has more to do with insufficient prewetting and some vagaries of agitation. The Expert tanks seem to take care of it for me.

  3. #23
    nick mulder's Avatar
    Join Date
    May 2005
    Shooter
    8x10 Format
    Posts
    1,204
    Images
    14
    Quote Originally Posted by outwest View Post
    The addition of the EDTA solution to PMK that Gordon recommends eliminates the oxidation problem. Probably not that anyway, as the worst blotching I had was with MaxPyro. I think it has more to do with insufficient prewetting and some vagaries of agitation. The Expert tanks seem to take care of it for me.
    Ridge 'blotching' ?

    I'm really trying to determine if what I'm talking about is the one and the same issue with the more 'standard' pyro/rotary issues... (which in true odd pyro manner I am yet to experience)
    Cleared the bowel problem, working on the consonants...

  4. #24
    outwest's Avatar
    Join Date
    Aug 2005
    Shooter
    Multi Format
    Posts
    312
    Images
    3
    Yes, from the ridges, or even the bumps on the old celluloid film holders for 2500 series tanks.

  5. #25
    nick mulder's Avatar
    Join Date
    May 2005
    Shooter
    8x10 Format
    Posts
    1,204
    Images
    14
    Ok - cool - thanks... Just trying to make sure we're all on the same page

    I'll be up and running soon once the E6 excitement dies down and I'll report back the test results ...
    Cleared the bowel problem, working on the consonants...

  6. #26
    nick mulder's Avatar
    Join Date
    May 2005
    Shooter
    8x10 Format
    Posts
    1,204
    Images
    14
    Efke 11x14" and Arista Edu 200 8x10", PMK+EDTA, pre-wet tubes, occasional lateral agitation, increased amount of chems...

    Base side streaks - cant be seen on either of the negs, but bang there they are in the prints

    I'm back to trays at midnight until I can try some Pyrocat-HD
    Cleared the bowel problem, working on the consonants...

  7. #27

    Join Date
    Jan 2005
    Location
    Washington, D.C.
    Shooter
    35mm
    Posts
    111
    Quote Originally Posted by sanking View Post
    Streaks and high b+f was reported in the very early days of PMK. The main issue is tht the developer oxidizes very rapidly. Solutions offered have been, 1) splitting the total volume of developer, discarding half of it at the mid-way point and adding the fresh, 2) adding a bit of sulfite to the working solution, or 3) adding some ascorbic acid to the working solution.

    All of these methods work, but Rollo Pyro and Pyrocat-HD and -MC work equally well without any of the above remedies and give results that are just as good as.

    The stain from the ridge marks is another issue, and is caused by agitation. It can be reduced or eliminated by, 1) using a much weaker dilution of the developer, with extended development time to compensate, or by 2) slowing down the rotation of the drum in RPM, or 3) by both 1 and 2.

    Sandy King
    I used a 1:2:250 dilution today and did a 30 minute semi-stand, agitating for the first minute and then at 15 minutes. No streaks. I love the results. It was with Foma 200 shot at ei 125.
    Last edited by damonff; 09-08-2013 at 08:10 PM. Click to view previous post history. Reason: spelling

  8. #28
    Rick Olson's Avatar
    Join Date
    Nov 2004
    Location
    U.S. Pacific Northwest
    Shooter
    Large Format
    Posts
    94
    Images
    9
    Hi Nick,

    I develop my 8 x 20 negatives in a 16 x 20 drum, using Pyrocat-HD by hand. Machine rotation caused too many problems. My solution to perfect negatives every time (using some of Sandy's tips):

    I have crafted/cut an acetate sleeve that is inserted into and covers all of the ribs in the drum.
    I only develop one sheet of 8 x 20 at a time.
    I use 2 liters of fresh developer per sheet.
    Rotation is by hand and slow at 4-5 revolutions per minute, with reversal of direction and gentle tilting.

    Good luck!
    Rick

Page 3 of 3 FirstFirst 123


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin