Darkroom humidity should be maintained in which range?

Darkroom humidity should be maintained in which range?

• A. between 20 and 30%
• B. between 70 and 80%
• C. between 40 and 60%
• D. between 5 and 10%

Answer: (C)

Humidity in the darkroom is kept around 40–60% to reduce static electricity during film handling. When air is too dry, static discharges can occur as you peel and move unexposed film, producing marks on the radiograph that mimic or obscure details. A moderate humidity level also helps minimize dust attraction and keeps handling conditions stable, while avoiding the condensation and other moisture-related issues that can occur if the air is too humid. This balance makes 40–60% the best range for maintaining image quality and minimizing artifacts.

Humidity in the darkroom is kept around 40–60% to reduce static electricity during film handling. When air is too dry, static discharges can occur as you peel and move unexposed film, producing marks on the radiograph that mimic or obscure details. A moderate humidity level also helps minimize dust attraction and keeps handling conditions stable, while avoiding the condensation and other moisture-related issues that can occur if the air is too humid. This balance makes 40–60% the best range for maintaining image quality and minimizing artifacts.