What adjusts the difference in appearance between light and dark areas of a photo?

The difference in appearance between light and dark areas of a photo is primarily adjusted through exposure settings, which control the amount of light that hits the camera sensor. Additionally, post-processing techniques such as contrast adjustment, brightness, and shadow/highlight manipulation can enhance or diminish these areas. The dynamic range of the camera sensor also plays a crucial role in capturing details in both highlights and shadows. Together, these factors influence the overall tonal balance in an image.