In processor QC, which instrument is used to evaluate sensitometric response?

• A. Sensitometer/densitometer evaluation
• B. Film calipers
• C. Dosimeter badge
• D. Geiger counter

Answer: (A)

Sensitometric response describes how a radiographic film’s density changes with exposure after it has been processed. In processor quality control, we evaluate this by performing sensitometry, which uses a sensitometer to expose a film in a controlled series of known exposures. After processing, a densitometer measures the resulting optical densities on the film. This combination—sensitometer to create the exposure steps and densitometer to read the densities—allows us to characterize the film’s speed and contrast and detect any processor-related changes. Other tools, like film calipers (measuring dimensions), dosimeter badges (occupational exposure), or a Geiger counter (radiation detection), don’t assess the film’s sensitometric response.