1. A system for producing a tomographic image using data acquired from a single detector row in a helical scan, said system comprising an x-ray source and a single slice detector array, a processor coupled to said detector array and configured to: generate a helical weighting factor based on a gantry angle and a detector angle, generate a modified weighting factor based on the generated helical weighting factor by shifting the helical weighting factor in the view angle direction, and apply the modified weighting factor to the data; wherein said modified weighting factor W.sub.f (.beta.,.gamma.) is: ##EQU3## where: .gamma. is the detector angle; .beta. is the gantry angle; W(.beta.,.gamma.) is the helical weighting coefficient; .DELTA..beta. is the shift along the view angle direction; and h(i) is the weighting applied to the ith shifted version, and h(i) is (-1,3,-1).