The volume per drop of the drops ejected by each nozzle is detected. It is then determined whether a volume of drops equal to or greater than a target value can be ejected by causing one or more first nozzles to eject drops, the detected volume per drop of the first nozzles falling within a first range of a preset value. When the determination is affirmative, the first nozzles are selected for ejection of drops. When the determination is negative, the first nozzles and one or more second nozzles are selected for ejection of drops. The detected volume per drop of the second nozzles falls within a second range of the present value, where the second range is greater than the first range.