It's threads like this one that separate this forum from the "equipment discussion" forums. This is great!(posted 8310 days ago)I don't have much to add except on Ilfosol-S shelf life. I tried it a couple of years ago and apparently bought a new bottle that was nearly dead. I don't know how long the developer had been on the shelf, but even with increased time and temperature, it was unable to develop films beyond a severely underexposed look.