A mode that offers simplified settings so that more users can enjoy the benefits of wireless multiple flash-unit photography. With existing Speedlights, users must rely on experience or prior knowledge to choose a flash level for remote flash units. The T043 offers a “quick wireless control mode” that allows users who lack experience or prior knowledge to intuitively set the flash level of two groups of flash units (A and B) by choosing the flash output ratio of each group (A : B).