Which factor directly impacts image quality by affecting the amount of scatter radiation?

The factor that directly impacts image quality by affecting the amount of scatter radiation is grid usage. Grids are used in radiography to absorb scatter radiation that occurs as x-rays pass through the patient and interact with tissues. Scatter radiation can degrade the quality of the image by reducing contrast and making it more difficult to see fine details.

When a grid is employed, it selectively allows the primary x-rays that carry diagnostic information to reach the image receptor while attenuating (absorbing) the scatter radiation. This results in a clearer, more detailed image because it enhances the contrast between different structures within the body.

While film processing time, patient positioning, and exposure duration can all influence image quality in various ways, they do not have the same direct effect on scatter radiation and its impact on image contrast as the use of grids.