I believe the value N corresponds to the m/z. I’ve noticed there may be an error between the value N in the image pane and the statistics pane. It seems the stats pane should be N+1 of the image pane.
Based on what I observed, N depends on the bin size and your mass range. For example when you convert your raw data files to an image, if your mass range is from 200-400 Da and your bin size is 0.1, then N=1 means m/z is 200, N=2 means m/z is 200.1, N=3 means m/z is 200.2 and …
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