The most suitable background color for displaying black and white photographs depends on various factors such as the mood of the overall shoot, high key or low key lighting, and tonality. A lighter background can evoke a softer feeling, while a darker background can create a more dramatic effect. Gray, with a value of 16.50, is often considered the best background color to use when displaying images as it helps to avoid the image appearing darker or lighter than it actually is due to the surrounding area acting as a light source. However, when adding a pop of color to a black and white photograph, the background color can be used to tell a story and draw the viewer's attention to a specific subject. Ultimately, the choice of background color should be based on the purpose of the photo and the desired effect.