To increase latitude for radiographing both thick and thin specimens at reasonable densities, what should be done?

The choice to load the film cassette with two films of different speeds is indeed a strategy to increase latitude when radiographing both thick and thin specimens. Using two films allows for capturing a broader range of densities on a single exposure, accommodating the varying levels of thickness and density present in the materials being inspected.

Thicker specimens usually require higher exposures to achieve sufficient film density, while thinner specimens might need less exposure to avoid overexposure. By employing films with different speeds, one can achieve contrast and detail across various thicknesses. For instance, a faster film could be used to take advantage of the lower exposure requirements of thin materials, while a slower film could capture the details in thicker materials that require higher exposure to prevent underexposure. This dual approach can help ensure optimum image quality across a variety of specimen thicknesses without having to change settings or redo exposures for each thickness.

In contrast, while a higher kV setting can help penetrate thicker materials, it does not necessarily address the issue of latitude in relation to different thicknesses on the same radiograph. Reducing the exposure time can lead to underexposure for thicker materials, and increasing the source-to-film distance, although it may improve image sharpness, also generally requires higher exposure settings, which