I've recently entered into the exciting realm of stand and semi-stand development. I've been using the Formulary's TFX-2 version of FX-2 at twice the normal dilution. My first attempt was with Pan F+ which gave me tantilizing if very high contrast negatives. My latest go has been with Acros. The resulting negatives are inspiring and the density range looks about perfect. They are also rediculously sharp.
The only problem is, I've just had my first ever run in with air bells! Little low density spot appearing in the sky region on about every other frame.
My agitation sceme was 60sec intial and 60sec at the 30 min mark, followed by an hour of full stand. I did NOT presoak. I certainly will next time, but my question is:
Are some films more prone to air bells than others?
I remember hearing at some point that Ilford doesn't recommend presoaking their films as they apply a wetting agent to the emulsion. My Pan F+ negs came out fine and the Acos negs were littered with air bells, both with equal development technique...