An image pickup system includes a thermography camera configured to pick up an image of an infrared light band, and a processor. The processor detects, from a difference in a temperature distribution between a thermography image for a subject obtained by image pickup of the subject using the thermography camera and a reference thermography image obtained by image pickup of the subject using the thermography camera, a change amount in the temperature distribution of the subject, detects a changed area of the subject where the detected change amount is a predetermined value or more, and generates a display image for displaying information about the detected changed area on a monitor.
