A CT imaging system includes a rotatable gantry having an opening to receive an object to be scanned, a first x-ray emission source attached to the rotatable gantry and configured to emit x-rays toward the object, and a second x-ray emission source attached to the rotatable gantry and configured to emit x-rays toward the object. A first detector is configured to receive x-rays that emit from the first x-ray emission source, and a second detector configured to receive x-rays that emit from the second x-ray emission source. A first portion of the first detector is configured to operate in an integration mode and a first portion of the second detector is configured to operate in at least a photon-counting mode.