Printing apparatus, printing system, printing method, and non-transitory recording medium

A printing apparatus comprising:

• a print execution device including a plurality of heads to print an image on a print medium based on print data;
• an illumination device, positioned downstream of the plurality of heads, to irradiate the printed image on the print medium with illumination light from behind a printed face of the print medium;
• a sheet ejection guide, wherein the illumination light is emitted from behind the printed face onto the printed surface of the print medium ejected by the sheet ejection guide from the printing apparatus;
• a winder positioned below the illumination device and at a downstream of the sheet ejection guide, wherein the winder is configured to pull the print medium ejected by the sheet ejection guide downward;
• and
• circuitry configured to determine an irradiation condition, which includes at least one of a position of a light source of the illumination light or a range of the light source of the illumination light, based on attribute information of the print medium, wherein the attribute information is information indicating a width of the print medium in a direction orthogonal to a conveyance direction in which the print medium is conveyed,
• wherein the illumination device emits the illumination light based on the irradiation condition,
• wherein the circuitry is configured to:
• receive an input of a usage environment of the print medium;
• and
• determine the irradiation condition based on the attribute information and the usage environment.