Situation The following procedure is to show a mirrored plot or an inverted plot or signal in MassHunter Qualitative Analysis. Solution Start with a simple signal you want to “invert”. Extract a signal that doesn’t exist, here I extracted an EIC of m/z = 1000, where there is no signal. Now perform a subtraction of the desired chromatogram to invert it. on the background chromatogram as indicated in the figure below, then select Subtract Any Chromatogram , then in the desired chromatogram (the one you want inverted). In this example the TIC was used; hence on this plot. The inverted TIC signal is created Superimpose the images and you get a version of the mirror plot.