Measurement position determination apparatus, image display system, and non-transitory computer readable medium

An image display system comprising:

• a creation unit that creates display image data for displaying a reference image and a comparison image on a display screen, the reference image including one achromatic image, the comparison image being formed by arranging two or more images including a chromatic image;
• a display that displays the reference image and the comparison image on the display screen in accordance with the display image data created by the creation unit;
• a measurement unit that measures the reference image and the comparison image in a sub-area on the display screen, the reference image and the comparison image being displayed on the display screen in accordance with the display image data;
• and
• a determination unit that determines a measurement position of the measurement unit on the display screen in accordance with measurement results obtained by measurement of the reference image and the comparison image using the measurement unit.