How does organic film grain differ from structured digital noise in image rendering?
Grain varies organically in size and distribution based on the film stock
The difference between film grain and digital noise is fundamentally rooted in their physical origins. Film grain originates from the physical structure of silver halide crystals suspended in the emulsion layer of the film. Because the size and distribution of these microscopic crystals vary depending on the specific chemical formulation of the film stock—such as whether it is a high-speed or low-speed emulsion—the resulting grain pattern is inherently organic, displaying variations in texture across the image area. Conversely, digital noise results from electronic imperfections in the sensor's operation. It tends to be more uniform and mathematically structured because it is tied to the regular grid pattern of the digital sensor elements, lacking the inherent randomness and physical texture found in silver halide distribution.
