Numerous comparisons have been made between noise and grain, and in a sense this is understandable because of the relationship between sensitivity/film speed and the amount of noise.
However, there the similarities end, as not only are the causes different, but so are the treatments. Indeed, the one good thing about noise in digital photographs is that it can be dealt with. Not perfectly and not easily, but there are various solutions.
In order to treat noise, we have to define it, and this isn’t as simple as it might seem. Technically, noise is artifacts or errors introduced into the image by electrostatic charge, and the scientific approach to it revolves around the signal-to-noise ratio. However, this does not take into account the very ...