Which of the following is NOT a concern when selecting film for photography?

When selecting film for photography, the ISO rating is a fundamental consideration, as it indicates the film's sensitivity to light. A higher ISO rating allows for better performance in lower light conditions, whereas a lower ISO is suited for bright environments. Knowledge of ISO helps photographers choose the right film for their intended shooting scenarios.

Aperture setting refers to the opening in a camera lens that controls the amount of light entering the camera and impacts depth of field. While it influences exposure, it is not a characteristic of the film itself but rather a setting on the camera that interacts with the film.

Shutter speed is another critical setting that determines how long the camera's shutter remains open to allow light to hit the film. Like aperture, shutter speed adjusts the exposure but does not directly relate to the choice of film.

In contrast, allergic reactions to chemicals used in film processing are typically not a direct concern when selecting the film type itself. While photographers should be aware of any personal sensitivities to chemicals, this consideration is less about the film selection process and more about handling and developing practices. Therefore, this option is deemed not a primary concern compared to the technical aspects of ISO, aperture, and shutter speed that directly influence the outcome of the photographic process.