How To Develop Film. Base fog is an overall cloudiness that occurs to film as it breaks down & ages, heat, humidity, background radiation all take their toll on film stock as it ages. The first chemical to go in is the developer.
The first chemical to go in is the developer. The trick with aged stock is to develop the film and not the base fog. Slowly pour enough of the developer into the central funnel of the processing tank and securely fit the flat lid.