Rolling shutter imaging control is performed so that an all-line exposure period (Ta) and a non-all-line exposure period (Tr) occur, and in the first light control mode, a first period ( In the second period (T2) consisting of the all-line exposure period (Ta) and the non-all-line exposure period (Tr) other than the first period (T1) while maintaining the light intensity of the illumination light at T1) at a predetermined level. An imaging system that controls the light source of illumination light so that the amount of illumination light is increased or decreased (CI1, CI2) compared to the immediately preceding second period (T2).全ライン露光期間（Ｔａ）と非全ライン露光期間（Ｔｒ）とが生じるようにローリングシャッタ方式の撮像制御を行い、第１調光モードにおいて、全ライン露光期間（Ｔａ）中の第１期間（Ｔ１）における照明光の光量を所定のレベルに維持しながら、第１期間（Ｔ１）以外の全ライン露光期間（Ｔａ）および非全ライン露光期間（Ｔｒ）でなる第２期間（Ｔ２）中における照明光の光量を直前の第２期間（Ｔ２）に比して増減させる（ＣＩ１，ＣＩ２）ように照明光の光源を制御する撮像システム。
