Radiography system

A radiography system comprising:

• a radiation source that emits radiation;
• a radiographic image detector that receives the radiation and detects a radiographic image;
• a portable retainer that holds the radiographic image detector and includes an inclination change mechanism which is configured to change an inclination of the radiographic image detector with respect to the radiation source;
• and
• a first detection mechanism that detects an inclination of the radiographic image detector about a first axis which intersects a vertical axis and which is directed toward the radiation source in a case in which a detection surface for the radiation in the radiographic image detector and the radiation source are disposed to face each other,
• wherein the radiography system further comprises a first processor,
• wherein the first detection mechanism comprises a string that hangs down in a direction parallel to the vertical axis and a first camera that images the string,
• wherein the first processor analyzes an image including the string captured by the first camera to detect the inclination of the radiographic image detector about the first axis, and
• wherein the inclination change mechanism comprises a telescopic movable portion and a lock portion configured to secure the movable portion.