At least one image pickup system that acquires distance information and prevents missing, or loss of, information while taking countermeasures against flicker, includes a first image pickup apparatus, a second image pickup apparatus, and a signal processing unit configured to process signals acquired from the first image pickup apparatus and the second image pickup apparatus. An exposure period of the first image pickup apparatus and an exposure period of the second image pickup apparatus are repeated a plurality of times in one frame. The exposure period of the first image pickup apparatus is overlapped with a non-exposure period of the second image pickup apparatus, and a non-exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus.