An imaging system comprising: a first imaging apparatus including a first imaging element in which a plurality of imaging pixels are arranged in a matrix and a first optical system that forms an image of a predetermined first region on an imaging surface of the first imaging element; a second imaging apparatus including a second imaging element and a second optical system that forms an image of a second region on an imaging surface of the second imaging element, the second region partially overlapping the first predetermined region; and a generator that generates a combined image based on image data acquired from the first imaging element and the second imaging element, wherein the first optical system includes a first free-form surface lens that has a shape that causes the image of the first predetermined region to be formed on the imaging surface of the first imaging element such that a resolution is different between an overlapping portion of the first predetermined region that overlaps the second region and another portion of the first predetermined region, and in the first predetermined region, the overlapping portion with the second region is a high-resolution portion of the first region having a resolution higher than a resolution of the other portion of the first predetermined region, the second optical system includes a second free-form surface lens that has a shape that causes an image of the second region on the second imaging element such that, in the second region, an overlapping portion with the first predetermined region has a resolution lower than another portion of the second region that does not overlap with the first region and is a high-resolution non-overlapping portion of the second region, and the generator combines image data of the high-resolution overlapping portion of the first region with image data of the high-resolution non-overlapping portion of the second region to generate a combined image. a first imaging apparatus including a first imaging element in which a plurality of imaging pixels are arranged in a matrix and a first optical system that forms an image of a predetermined first region on an imaging surface of the first imaging element; a second imaging apparatus including a second imaging element and a second optical system that forms an image of a second region on an imaging surface of the second imaging element, the second region partially overlapping the first predetermined region; and a generator that generates a combined image based on image data acquired from the first imaging element and the second imaging element, wherein the first optical system includes a first free-form surface lens that has a shape that causes the image of the first predetermined region to be formed on the imaging surface of the first imaging element such that a resolution is different between an overlapping portion of the first predetermined region that overlaps the second region and another portion of the first predetermined region, and in the first predetermined region, the overlapping portion with the second region is a high-resolution portion of the first region having a resolution higher than a resolution of the other portion of the first predetermined region, the second optical system includes a second free-form surface lens that has a shape that causes an image of the second region on the second imaging element such that, in the second region, an overlapping portion with the first predetermined region has a resolution lower than another portion of the second region that does not overlap with the first region and is a high-resolution non-overlapping portion of the second region, and the generator combines image data of the high-resolution overlapping portion of the first region with image data of the high-resolution non-overlapping portion of the second region to generate a combined image.