1. A tomographic system comprising: a gantry having an opening for receiving an object to be scanned; a radiation source; a detector positioned to receive radiation from the source that passes through the object; and a computer programmed to: acquire a plurality of helical projection datasets of the object; reconstruct a first image using the acquired plurality of helical projection datasets and using a first reconstruction algorithm; reconstruct a second image using the acquired plurality of helical projection datasets and using a second reconstruction algorithm that is different from the first reconstruction algorithm; extract frequency components from each of the first and second images; sum the frequency components from each of the first and second images; and inverse transform the sum of the frequency components to generate a final image.