Classic STP Indicator stop bath...when broken?

Beef · 2009-04-08T10:23:46+00:00

Hi, schon immer verwende ich das Classic STP Indicator-Stoppbad hier aus dem Shop. Normalerweise hab ich das Stoppbad immer neu angesetzt, wenn ich neuen F...

Beef

Hi, I’ve always used the Classic STP Indicator stop bath from this shop. I’ve usually made a fresh batch of the stop bath whenever I’ve prepared a new fixer. But now I’ve decided to put it to the test and see how long the stop bath actually lasts. According to the description: “If the colour of the solution changes from orange/yellow to green-blue/violet, the bath is used up...” Well, I actually do quite a lot of development and prepared my current stop bath about 3–4 months ago...it’s still bright yellow :lol: Could it be that you can’t rely on this, or does the stop bath simply last that long? My developers: Eukobrom and Dokumol, or Rodinal and HC-110 Regards Andi

Tandemfahren

Hi Andi, I don’t use this stop bath myself, but it’s easy enough to test whether the indicator works: just whisk a small amount of it with an alkaline solution until it changes colour. Or maybe not (though I’d bet it does). Incidentally, it’s strongly recommended that you use separate stop and fix solutions for film and paper respectively (but who stops film anyway? – except for Orthopan UR or ATP, which are used with a diluted solution anyway), if only because of the ghastly colour that some films impart to the prints, and which I don’t want to see in my pictures. The lifespan depends quite a bit on your draining habits, apart from the amount of paper, of course. Good light Frank

mdeutgen

But who actually stops films?

I do, for example, at the moment. But that’s mainly because I’m currently using X88/X89 fixer, and with this neutral fixer, a stop bath is absolutely essential... When I work with an acidic fixer, I prefer to rinse twice in between rather than use a stop bath. Martin