If the exposure field is not accurately recognized, the histogram will contain data:

• A. Outside the exposure field, narrowing the histogram
• B. Inside the exposure field, widening the histogram
• C. Outside the exposure field, widening the histogram
• D. Inside the exposure field, narrowing the histogram

Answer: (C)

In digital radiography, the histogram represents how pixel values are distributed across the entire image and is used to adjust brightness and contrast. If the exposure field isn’t accurately recognized, data from outside the irradiated area—where there was little or no exposure—gets included in the histogram. Those outside-field pixels have very low values, while the inside-field pixels have higher values. Mixing these distinct regions broadens the distribution, so the histogram widens.