This International Standard specifies an instrumental method for determining the image clarity of anodic oxidation coatings on aluminium and aluminium alloys by measuring reflection from the surface with the help of a sliding combed shutter.The test can only be applied to a flat surface which can reflect the image on the limited combed shutter and photo-receiver. This method can also measure the optical evenness of anodic oxidation coatings on aluminium and aluminium alloys.