Which statement about film plane parallelism is TRUE?

Film plane parallelism is a crucial concept in photography, particularly in ensuring the sharpness and overall quality of the image captured. The correct answer emphasizes that the lens should be positioned so that it is perpendicular to the subject. This alignment ensures that the entire subject is in focus, as light rays entering the lens from the subject can be accurately directed onto the film or sensor.

When the lens is perpendicular to the subject, it minimizes distortion and allows for an even distribution of sharpness across the image. This is especially important in situations where depth of field plays a significant role, such as landscape photography or architectural shoots, where one aims for maximum detail from front to back.

In contrast, alternatives that suggest keeping the film plane horizontal, at an angle, or that involve diagonal lens positioning would compromise image quality. These positions can lead to tilting effects, unintentional distortion, and uneven focus, all of which negatively impact the overall image integrity.