Types of noise
2The two main types of noise: chroma or colour, which look like small coloured blotches and flecks and luminance noise, which is the grainy appearance you can see. Both of these increase as the ISO level is raised, and at the highest levels images can become practically unusable. It’s difficult to pinpoint when image quality drops because all cameras handle noise differently, although generally the more expensive professional cameras produce less noise at higher ISO levels.