An image taking system including: (a) a CMOS or CCD image sensor; (b) an interest-region setter configured to set regions of interest within an image taking area of the image sensor; (c) an acquiring-condition determiner configured to determine an image-data acquiring condition required for acquiring at least two image data generated in at least two of the regions of interest; and (d) an image-data acquirer configured to acquire the at least two image data. The acquiring-condition determiner includes an exposure-time determining portion configured to determine, as the image-data acquiring conditions, at least two different exposure times required for acquiring the at least two image data generated in the at least two regions of interest. The image-data acquirer includes an exposure-time-based-image-data acquiring portion configured to acquire the at least two image data, such that the acquired at least two image data are based on the at least two different exposure times. Also disclosed is an electronic-circuit-component mounting machine that includes the image taking system.