Image reading apparatus and image forming apparatus

An image reading apparatus, comprising:

• a pair of guide plates arranged in perpendicular with a conveying direction of an original placed on an original tray to sandwich an end of the original in a width direction;
• a guide width measuring unit configured to measure a width between the guide plates with the original sandwiched as a guide width;
• a tray on which an original is to be placed;
• a conveyer configured to convey the original;
• a reading unit configured to read the original being conveyed by the conveyer;
• a first sensor configured to detect a width of the original being conveyed by the conveyer as an original width;
• a second sensor configured to detect an amount of inclination of the original being conveyed by the conveyer;
• an inclination correcting unit configured to correct an image of the original read by the reading unit in accordance with the amount of inclination detected by the second sensor;
• and
• a controller configured to determine an inclination correction condition for the image of the original, and to compare the guide width detected by the guide width measuring unit with the original width detected by the first sensor and control whether or not to perform an inclination correction by the inclination correcting unit in accordance with a result of the comparison and based on an inclination correction condition for the image of the original,
• wherein, in a case where an amount of inclination of the original is more than a predetermined value and width of the original detected by the first sensor is less than a value corresponding to the width between the guide plates detected by the guide width measuring unit, the inclination correction by the inclination correcting unit is not performed.