Endoscope system that displays two still images of a subject illuminated by two types of lights having different wavelength bands

An endoscope system comprising:

• a light source that alternatingly emits first illumination light and second illumination light at a predetermined cycle, the first illumination light and the second illumination light having different wavelength bands;
• an imaging sensor that images a subject illuminated by the first illumination light and generates a first image signal, and that images the subject illuminated by the second illumination light and generates a second image signal;
• a first memory that successively stores generated first image signals;
• a second memory that successively stores generated second image signals;
• a processor that performs operations including:
• calculating first image evaluation values based on the stored first image signals;
• calculating second image evaluation values based on the stored second image signals, independently of the first image evaluation values;
• selecting a first display image signal from the stored first image signals, based on the calculated first image evaluation values;
• and
• selecting a second display image signal from the stored second image signals, based on the calculated second image evaluation values, the second display image signal being selected independently of the first display image signal;
• and
• a display that displays a first image that is based on the first display image signal and a second image that is based on the second display image signal at the same time;
• wherein the first display image signal is selected independently of the second image signal evaluation values, and the second display image signal is selected independently of the first image signal evaluation values.