1. A method of performing imaging mass spectrometry of a sample, the method comprising: performing a first mass analysis of the sample using a first mass analyzer comprising a multi-pixel ion detector to obtain first mass spectral data representative of pixels of the sample; identifying clusters of pixels sharing one or more characteristics of first mass spectral data; and performing a second mass analysis of the sample using a second mass analyzer to obtain second mass spectral data at at least one location in each cluster, wherein the second mass analysis being of higher resolution than said first mass analysis, wherein ionization conditions for the first mass analyzer are different from ionization conditions for the second mass analyzer.