Which action reduces motion unsharpness?

Which action reduces motion unsharpness?

• A. Increasing patient motion
• B. Decreasing exposure time
• C. Decreasing SID
• D. Increasing exposure time

Answer: (B)

Motion unsharpness comes from the patient moving during the X-ray exposure. The key to reducing it is to minimize the time the X-ray beam is active, so there’s less opportunity for movement to blur the image. Shortening the exposure time does just that—limits movement during capture and yields a sharper image. Increasing patient motion obviously increases blur. Decreasing SID mainly affects geometric factors like magnification and penumbra rather than motion, so it doesn’t address motion blur. Increasing exposure time lengthens the moment the patient could move, which increases blur instead of reducing it.

Motion unsharpness comes from the patient moving during the X-ray exposure. The key to reducing it is to minimize the time the X-ray beam is active, so there’s less opportunity for movement to blur the image. Shortening the exposure time does just that—limits movement during capture and yields a sharper image.

Increasing patient motion obviously increases blur. Decreasing SID mainly affects geometric factors like magnification and penumbra rather than motion, so it doesn’t address motion blur. Increasing exposure time lengthens the moment the patient could move, which increases blur instead of reducing it.