What factor does not contribute to underexposure of a radiograph?

Underexposure of a radiograph occurs when the film or digital detector receives insufficient radiation, resulting in a dark image. The factors that primarily influence the amount of radiation received include milliamperage (mA), exposure time, and kilovoltage (kV).

Milliamperage directly affects the quantity of radiation produced; higher mA settings increase the number of x-ray photons generated, which helps in achieving adequate exposure. Similarly, exposure time dictates the duration for which the x-ray beam is active, thus directly influencing the total radiation received by the image receptor. Kilovoltage determines the quality and penetrating power of the x-rays; higher kV settings increase the energy of the x-ray beam, enabling it to penetrate the subject more effectively and reach the image receptor.

On the other hand, Source-to-Image Distance (SID) refers to the distance between the x-ray source and the image receptor. While SID can affect the intensity of the radiation reaching the receptor according to the inverse square law, it does not inherently contribute to underexposure in the same manner as the other factors do. In fact, increasing the SID can lead to decreased radiation intensity, but it is the combination of mA, exposure time, and kV that are