Which statement regarding filtration and image contrast is true?

• A. Filtration Increases Image Contrast
• B. Filtration Decreases Image Contrast
• C. Filtration Has No Effect On Image Contrast
• D. Filtration Varies With Technique

Answer: (A)

Filtration changes the quality of the X-ray beam by removing the lowest-energy photons, making the beam harder. Those low-energy photons tend to be absorbed more readily by the patient and to contribute to scatter and fog that wash out image detail. When you filter them out, fewer photons reach the detector as scatter, so the background noise decreases and the edges between different tissues become more distinct. The result is an image with improved visibility of structure differences, which is interpreted as increased image contrast. Remember that this comes with a drop in overall receptor exposure, so technique may need adjustment to maintain image brightness while preserving the contrast improvement.