How can a larger physical size source produce an equivalent quality radiograph?

A larger physical size source can produce an equivalent quality radiograph by increasing the source-to-film distance. This method effectively mitigates the effects of the larger source size, specifically the penumbra effect, which can cause blurriness in the radiograph due to the geometric spread of the radiation being emitted from the source.

By increasing the distance between the source and the film, the spreading of the radiation rays over a longer distance leads to a more focused and less blurry image. The rays converge more sharply on the film, thus enhancing the image sharpness and enabling clearer details to be recorded, which is crucial for accurate inspections.

The other options—such as using a faster film, reducing exposure time, and using a different developer—could influence the sensitivity and quality of the radiographic image, but they do not directly address the challenge posed by a larger source size. The adjustments mentioned in those options could potentially improve image quality in other contexts, but they don't solve the issue related specifically to the impact of the size of the radiation source on image clarity.