How can excessive subject contrast due to thickness range in a test specimen be corrected?

The correct answer involves increasing the kilovoltage and using a filter at the X-ray tube, which effectively addresses excessive subject contrast resulting from the thickness of the specimen being tested.

When the kilovoltage is increased, it enhances the penetrating power of the X-ray beam. This means that the beam can pass through thicker areas of the specimen more effectively, reducing the contrast differences that occur because of varying thickness. Thicker sections may otherwise absorb more radiation, leading to darker areas on the radiograph. By increasing the kilovoltage, you reduce the likelihood of variable density caused by thickness, which standardizes the radiographic result.

Additionally, incorporating a filter at the X-ray tube helps to refine the beam, allowing lower-energy, less penetrating X-ray photons to be absorbed, while allowing high-energy photons to pass through. This further promotes even exposure across varying thicknesses, again aiding in reducing excessive subject contrast.

In contrast, decreasing the kilovoltage or using lower radiation energy would only exacerbate the issue, as it would reduce the penetrative force of the X-rays, potentially increasing the variability in exposure across the specimen. Reducing exposure time does not address the fundamental problem of subject contrast related to thickness; it simply affects how long the X-ray