Image forming apparatus

A method, comprising:

• detecting, by a first detection system of an image forming system, whether there is at least one abnormality on a surface of a cylindrical photoreceptor system at a first position;
• causing, by a controller of the image forming system, a second detection system to start detecting whether there is the at least one abnormality on the surface of the cylindrical photoreceptor system at a second position, wherein detecting starts at a point in time after a waiting time, wherein the waiting time corresponds to a time for the cylindrical photoreceptor system to rotate by a distance between the first position and the second position subsequent to the first detection system starting the detection of the at least one abnormality;
• and
• determining, by a determination system of the image forming system, damage occurred at a surface position of the surface of the cylindrical photoreceptor system when the second detection system detects the at least one abnormality at the surface position of the cylindrical photoreceptor system at which the first detection system detected the at least one abnormality.

An image forming system, comprising:

• a cylindrical photoreceptor system configured to have a rotational shaft in a longitudinal direction;
• a controller configured to cause a second detection system to start detecting of at least one abnormality at a point in time after a waiting time, wherein the waiting time corresponds to a time for the cylindrical photoreceptor system to rotate by a distance between a first position and a second position subsequent to a first detection system starting a detection of the at least one abnormality;
• and
• a determination system configured to determine a defect occurred at a surface position of a surface of the cylindrical photoreceptor system when the second detection system detects the at least one abnormality at the surface position of the cylindrical photoreceptor system at which the first detection system detected the at least one abnormality.