Archived posting to the Leica Users Group, 2002/03/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Supposedly the pinhole problem mainly occurred with older developers that used sodium carbonate as the alkali. It formed carbon dioxide gas when it hit the acid stop bath. Carbonate in developer is pretty uncommon these days. For what its worth though I just use two water rinses with continuous agitation for 15 seconds each and it works just fine for me. Mike D - ----- Original Message ----- From: "Frank Filippone" <red735i@earthlink.net> To: <leica-users@mejac.palo-alto.ca.us> Sent: Monday, March 25, 2002 10:48 AM Subject: RE: [Leica] Darkroom Question > You stand the chance of getting bubbles from an overly active stop bath. > The bubbles act as little pin holes in the negs. There is a lot of > commentary about the phenomenon, some say it happens, others say it is > impossible. Something happened to me just once, and I do not use the acid > stop any more. > > Bottom line, in understanding the chemistry of the stop bath..... > Developers work in alkaline environments. The purpose of the stop is to > make the environment acidic, such that the developer action is immediately > stopped. This gives you a consistent process. > > Use 1/2 the amount of stop as you might think, it is still enough. I > personally have switched to a water rinse ( no acid stop) between developer > and fix. > > Frank Filippone > red735i@earthlink.net > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html > - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html