an image-forming apparatus configured to form an image on a sheet;

a reading apparatus configured to read, via a transparent member, an image formed on a sheet conveyed from the image-forming apparatus to obtain read image data; and

at least one processor configured to:

(1) control the image-forming apparatus to form a test chart that is a predetermined image on a first sheet,

(2) calibrate, using first read image data obtained by the reading apparatus reading the test chart on the first sheet, second read image data that is obtained by the reading apparatus reading an inspection target image formed by the image-forming apparatus on a second sheet based on RIP data, and

(3) inspect the inspection target image based on the calibrated second read image data and the RIP data,

wherein the test chart includes (a) a patch arrangement with a plurality of patches and (b) a low brightness region that at least partially surrounds the patch arrangement, and

wherein a size of a periphery patch located at a periphery of the patch arrangement is smaller than a size of an interior patch located further inside than the periphery patch.