Dante_Stella
Rex canum cattorumque
I have had this problem for 20 years - so I guess it's time to ask. When I open the lid of a developing tank to "burp" it after initial agitation, the tank spits out copious amounts of what looks like soap suds (without regard to what developer is in use).
I've eliminated the possibility of leaving Perma-Wash or Photo-Flo on reels or in the tank - so what gives? Does 120 film have a surfactant coating that promotes wetting and causes this? It only really happens in the developing stage.
Fortunately, this has not caused marks on the film, but it sure makes a mess, especially with Rodinal - where huge amounts of purple-Kool-Aid-looking developer (+film antihalo dye) come out with the bubbles.
I've eliminated the possibility of leaving Perma-Wash or Photo-Flo on reels or in the tank - so what gives? Does 120 film have a surfactant coating that promotes wetting and causes this? It only really happens in the developing stage.
Fortunately, this has not caused marks on the film, but it sure makes a mess, especially with Rodinal - where huge amounts of purple-Kool-Aid-looking developer (+film antihalo dye) come out with the bubbles.