Printing apparatus and control method

A control method of a printing apparatus including:

• a carriage in which a print head configured to perform printing by ejecting ink to a conveyed print medium is mounted, the carriage movable in a width direction of the print medium intersecting a conveyance direction of the print medium;
• a first detection unit provided in the carriage and including a light emitting part configured to emit light to the print medium and three light receiving parts configured to receive reflected light from the print medium and provided at positions varying from one another in the width direction, the first detection unit capable of being switched between a first mode in which the first detection unit detects an end portion of the print medium based on an output corresponding to an amount of received light in one of the light receiving parts and a second mode in which the first detection unit detects the end portion based on a difference between outputs corresponding to amounts of received light in two of the light receiving parts not used in the first mode;
• an obtaining unit configured to obtain position information of the end portion based on an output from the first detection unit in the first mode and obtain the position information of the end portion based on an output from the first detection unit in the second mode;
• and
• an adjusting unit configured to execute first output adjustment in which the adjusting unit adjusts the output from the first detection unit in the first mode and second output adjustment in which the adjusting unit adjusts the output from the first detection unit in the second mode, the control method comprising:
• a first adjustment step of executing the first output adjustment;
• and
• a second adjustment step of executing the first output adjustment and the second output adjustment, wherein
• the first adjustment step is executed before execution of first printing in which the position information of the end portion is not obtained during printing, and
• the second adjustment step is executed before execution of second printing in which the position information of the end portion is obtained during printing.