1. An imaging system comprising: a source generating an x-ray beam; a detector array receiving said x-ray beam and generating projection data; a translatable table configured for disposal of an object thereon and operable to translate in relation to said source and said detector array; said source and said detector array rotating about said translating table to helically scan said object; an image reconstructor electrically coupled to said detector array, said image reconstructor having a processor responsive to executable computer instructions when executed on the processor for performing a first reconstruction to reconstruct a first image in response to said projection data via a first iterative reconstruction technique; and, wherein said image reconstructor is further responsive to executable computer instructions for performing a second reconstruction of a second image in response to said first image via a second iterative reconstruction technique; and wherein said first iterative reconstruction technique converges on said data with lower spatial frequencies faster than on data with higher spatial frequencies, and said second iterative reconstruction technique converges on said data with higher spatial frequencies faster than on data with lower spatial frequencies.