Ilford IS-1 Acetic Acid Stop Bath
Intended for use with films, plates and papers.
Water . . . 500cc
Acetic Acid, Glacial . . . 17ml
Add water to make . . . 1 litre
Films, plates and papers should be immersed in this bath for about five seconds under constant movement.
This stop bath will need to be replaced when it reaches a pH of 5.8. This may be determined by using BDH Narrow range indicator paper 5570 or a suitable substitute.