There is provided an image detecting system including an image detecting section that detects a moving image of an examination subject into which a radiopaque contrast medium flows through one of an artery and a portal vein, and a change image generating section that generates a change image representing a change in the moving image. Here, the change is caused by movement of the radiopaque contrast medium after a timing at which the radiopaque contrast medium that has flown into one of the artery and the portal vein flows into capillaries.