The Film Grain tool can be used to alter the image aesthetic by adding a realistic interpretation of film grain to digital images. Alternatively, the Grain tool may be used to add texture to digital images that have an excessively smooth or “polished” appearance, possibly after adding too much noise reduction or after adjusting the negative Clarity settings. If this is the case, the Film Grain tool may be used to create a more natural-looking image. Increase Impact (contrast) and Granularity (grain size) with caution. A number of built-in presets for different grain-effects are available from the tool's action menu (...).
NOTE: In Capture One Express, the Film Grain tool is not present.