Which process corrects slight under-exposure or over-exposure errors made by the technologist?

• A. Rescaling
• B. Histogram analysis
• C. Lookup table (LUT) adjustments
• D. Digitization

Answer: (A)

When you have a digital radiograph that’s just a bit too dark or too light, rescaling adjusts the image after capture by applying a simple linear change to all pixel values. This shifts the overall brightness and density so the image looks as if the exposure was more appropriate, without needing another exposure. It’s the most direct way to correct slight exposure errors because it realigns the entire image’s grayscale values to the display range while preserving diagnostic detail. Histogram analysis checks the distribution of gray levels to guide processing but doesn’t by itself change brightness. Look-up table adjustments map pixel values to display intensities to affect contrast and appearance, but they aren’t the primary method for correcting exposure error. Digitization is the conversion from the analog signal to digital data, not a correction step.