MCC or Varitone in Adostop 1+10 hissing noise after 25 sec

kaleun12 · 2010-01-11T14:18:12+00:00

Hallo, ich stelle regelmäßig fest, dass bei mir bei den Barytpapieren Adox MCC oder Variotone nach ca. 25 Sekunden im Stoppbad (Adostop 1+10) ein Zischgeräu...

kaleun12

Hello, I regularly notice that when I use Adox MCC or Variotone baryta papers, a hissing sound occurs after about 25 seconds in the stop bath (Adostop 1+10); this does not happen with PE paper. My questions are: Where does the noise come from? Should I be concerned enough to remove the paper from the stop bath before the noise starts or after it stops, or is it not worth worrying about at all? Many thanks, Torsten

GeorgK

Hello. That must be carbonate (developer alkali) outgassing as CO₂ in the acidic stop bath. It’s also a sign that the paper is now soaking up the stop bath really well. I think a 1+10 stop bath is unnecessarily strong, and 25 seconds is already the upper limit (why do we always have to overdo everything?). Adostop has an indicator anyway, so feel free to go down to 1+40; there’s no risk of it tipping over unnoticed. Regards, Georg

kaleun12

Hi Georg, I’ve followed the instructions on the packet regarding dilution and time. Will I still achieve the desired result at 1+40, and how do I actually know that development will definitely stop at a specific dilution and time? Is there any way to test this? I’ll soon be using a Jobo Drum for paper development and have read on the website http://www.stefanheymann.de/foto/sw-mit-drum.htm that a stop bath isn’t actually necessary, which presumably refers more to the fact that, given the small amount of chemicals, you use single-use batches, right? Regards, Torsten

michael-kielgmxnet

Hello Torsten, I’m familiar with that hissing sound too, particularly when using Maco Expo paper. Like you, I stop the development with a 1:20 dilution for about 30 seconds. I think the need for a stop bath depends primarily on the fixer used. If you use a neutral or alkaline fixer, you should definitely use a stop bath; with an acidic fixer, this isn’t necessary, or a quick rinse is sufficient. When using lith printing, it is also essential to use a stop bath, as you then need to stop the development process precisely ‘on the dot’. Incidentally, a neutral fixer is the better option for baryta paper, as you then do not need to wash out any acid during the final washing, which shortens the washing time. Best regards, Michael