On the Projection-Reconstruction NMR.∗

We discuss the recently proposed Hybrid Backprojection/Lower-Value (HBLV) algorithm and its implementation in the NMR projection-reconstruction software PR-CALC. We argue that the HBLV reconstruction is only suitable for spectra that have no negative peaks. However, in such cases HBLV becomes a straight-forward generalization of the Lower-Value reconstruction algorithm and boils down to a simple calculation, not requiring an expensive combinatorial search for the smallest sum as was originally suggested by the authors.