Page 4 of 4 FirstFirst ... 234
Results 31 to 33 of 33

Thread: Problem with Pyrocat HD from PF

  1. #31
    Andrej Gregov
    Join Date
    Nov 2010
    Location
    Seattle, WA
    Posts
    101

    Re: Problem with Pyrocat HD from PF

    See below for my ordeal. I emailed Formulary back in the Spring wanting to give feedback and help them solve whatever issue is going on. Not heard a peep from them. Maybe an email from the forum might get their attention. I believe they figure it's operator error, as Sandy states. But in my case, I did nothing different except change from Formulary to Bostick Pyrocat HD and development times snapped right into place for me. Sandy, have you used any stock Pyrocat from Formulary in liquid form? It might take someone of Sandy's reputation to get their attention.

    https://www.largeformatphotography.i...85#post1502485

  2. #32
    Cor's Avatar
    Join Date
    Nov 2006
    Location
    Leiden, The Netherlands
    Posts
    692

    Re: Problem with Pyrocat HD from PF

    My 2 cents: I always mixed my own Pyrocat-HDC (in Glycol) from the same chemistry stocks per instructions from Sandy King. A couple of years ago I suddenly started to get problems with solution "A"..a white precipitate on top (a contradiction), whch I could not get into solution again.

    So I switched to Pyrocat-HDC, no more problems.

    The funny thing is that I kept this bottle of HD and use it when I re-devlop in Pyro after bleaching a negative..it still works after a littleswirling to get a 'suspension"..

    best,

    Cor

  3. #33
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    1,797

    Re: Problem with Pyrocat HD from PF

    Quote Originally Posted by sanking View Post
    Nearly all of the issues associated with Pyrocat seem rooted in working procedures or operator error.

    Any developer that contains carbonate can develop sufficient gas to cause pinholes in film emulsion, especially if development is followed by an acetic acid stop bath. A working solution of Pyrocat has pH of about 11, when you change the film from this environment to an acetic acid stop bath with pH 4 or below, the shock to the emulsion is great. A better choice would be a water stop bath rather than an acetic acid stop bath.

    Pinholes used to be common with films and carbonate type developers but over the years emulsions have become much tougher and pinholes are very rare except with some old style traditional emulsions. But going from a very alkaline developing solution to a very acetic acid stop is capable of blowing holes in any emulsion.

    A water rinse gives about 100% protection from pinholes.

    Sandy
    The biggest offender for film was HP5. Next round I will try water stop bath and see how that does. The problem was worse for semi-stand over a 1 hour period. However, this last time I tried with Tmax100 as semi-stand worked out fine from what I can tell.

Similar Threads

  1. continuing pyrocat problem
    By Jbuck in forum Darkroom: Equipment
    Replies: 31
    Last Post: 19-Apr-2019, 15:40
  2. Problem with Pyrocat-MC
    By jon.leatherwood in forum Darkroom: Film, Processing & Printing
    Replies: 13
    Last Post: 11-Oct-2011, 23:06
  3. Pyrocat HD Problem
    By Richard Wasserman in forum Darkroom: Film, Processing & Printing
    Replies: 31
    Last Post: 13-Nov-2010, 23:36
  4. Problem with Jobo 3005, Pyrocat, TMY-2
    By Pfeiffer Duckett in forum Darkroom: Film, Processing & Printing
    Replies: 5
    Last Post: 7-Apr-2009, 17:13
  5. pyrocat hd problem
    By mike fitzgibbon in forum Darkroom: Film, Processing & Printing
    Replies: 6
    Last Post: 16-Oct-2007, 20:27

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •