Extended Data Fig. 1: Cardinal v.3 supports visualization and preprocessing of high mass resolution data.

a, Reproducing the overlay ion image of three m/z features with different spatial abundances (Fig. 1a in original publication). b, Zoomed in average mass spectra show two peaks that are only 0.05 m/z apart (Fig. 2c in original publication) and could be detected as separate peaks. The red dotted lines indicate that both peaks will be picked separately during peak detection. c, Visualizing the spatial distribution of both peaks shows that they are present in different tissue regions (Fig. 2b in original publication). The peaks in the original publication were likely mislabeled as suggested by Fig. S5 of the same publication and the inverse image we obtained here.