In an image capturing system, a lighting device includes a base disposed on a medium setting surface on which a medium serving as a reading target is set, an arm extending upward from the base, a top unit extending from the arm in such a manner that the top unit faces the medium setting surface, a placement surface that is provided to the top unit and on which a smartphone (imaging unit) is placed at a position allowing the smartphone to photograph the medium set on the medium setting surface, and a lighting LED that is provided to the top unit and irradiates the medium setting surface.