A number of deteriorated cellulose acetate/nitrate-based 35 mm cinematograph films have been studied by moisture regain, uv absorption, viscometry, pH, and degree of insolubilization. Analysis of naturally aged films indicates a correlation between moisture regain, acidity, and degree of degradation. Artificial aging studies at various temperatures and at different humidities show that temperature, moisture regain, and pH are important related factors in the degradation mechanism.