Which of the following maintains image brightness over a wide range of exposures?

Which of the following maintains image brightness over a wide range of exposures?

• A. AEC
• B. Bit Depth
• C. Automatic Rescaling
• D. Detector Size

Answer: (B)

Bit depth determines how many gray shades the image can represent. When exposures vary widely, having more bits means more tonal levels for storing brightness values, so you can capture subtle differences without clipping in bright areas or losing detail in dark areas. This keeps the image brightness and detail more consistent as exposure changes. For example, 8-bit provides 256 levels, while 12-bit or 16-bit systems offer thousands to millions of levels, greatly reducing posterization and preserving perceived brightness across exposures. Exposure control (AEC) can adjust exposure to hit a target brightness, and automatic rescaling can alter display brightness after capture, but neither changes the actual range of brightness levels that the detector can record. Detector size affects field of view and dose, not the number of gray levels available.

Bit depth determines how many gray shades the image can represent. When exposures vary widely, having more bits means more tonal levels for storing brightness values, so you can capture subtle differences without clipping in bright areas or losing detail in dark areas. This keeps the image brightness and detail more consistent as exposure changes. For example, 8-bit provides 256 levels, while 12-bit or 16-bit systems offer thousands to millions of levels, greatly reducing posterization and preserving perceived brightness across exposures. Exposure control (AEC) can adjust exposure to hit a target brightness, and automatic rescaling can alter display brightness after capture, but neither changes the actual range of brightness levels that the detector can record. Detector size affects field of view and dose, not the number of gray levels available.