Image forming apparatus and method for controlling image forming apparatus

An image forming apparatus comprising:

• a plurality of sheet feed trays on which a plurality of sheets are placed;
• a transferrer that transfers an image formed by an image forming part onto a sheet at a transfer position;
• a plurality of conveyance roller pairs provided along conveyance paths from the plurality of sheet feed trays to the transfer position and that conveys a fed sheet;
• a conveyance position detector that detects, at a position upstream of the transfer position, a conveyance position of a conveyed sheet in a width direction perpendicular to a conveyance direction;
• a sheet position adjuster that performs, at an adjustment position upstream of the transfer position, adjustment of the conveyance position of the sheet in the width direction by using an amount of displacement calculated from the detected conveyance position;
• a hardware processor that determines an amount of skew correction on the basis of a sheet feed tray that is to be used among the plurality of sheet feed trays, a sheet length of a sheet that is to be fed from the sheet feed tray, and the amount of displacement;
• and
• a skew corrector that performs skew correction by adjusting an image forming position before transfer on the basis of the amount of skew correction determined by the hardware processor.