An imaging system (1400) includes a first and a second focal spot (1410I and 1410N), a first pre-patient radiation beam filter (1416) disposed between the first focal spot and the examination region and having a first profile and a second pre-patient radiation beam filter (1416N) disposed between the second focal spot and the examination region and having a second profile, and a source controller (1412) that controls an operation of the focal spots by modulating the operation during a scan based on at least one of an angular position of focal spots, a shape of a region of interest of subject or object being scanned, or based on a change in size between two adjacent regions of the subject or object being scanned.