Image reading apparatus and image forming system

An image forming system comprising:

• a conveyance portion configured to convey a sheet;
• an image forming portion configured to form an image on the sheet being conveyed by the conveyance portion;
• and
• an image reading apparatus configured to read the sheet on which the image has been formed by the image forming portion,
• wherein the image reading apparatus includes:
• a reading unit configured to read the image formed on the sheet being conveyed by the conveyance portion;
• a reference member to be read by the reading unit at a time of performing shading correction;
• a transparent member, which is provided between the reading unit and a position at which the conveyance portion conveys the sheet, prevents foreign matter from adhering to the reading unit, and has the reference member attached to the transparent member;
• support members configured to support the transparent member at both ends in a direction intersecting a conveyance direction of the sheet being conveyed by the conveyance portion;
• and
• a moving portion configured to move the support members.