A method of ion imaging is disclosed comprising scanning a sample and acquiring first mass spectral data related to a first pixel location at a first spatial resolution and determining whether or not the first mass spectral data satisfies a condition. If it is determined that the first mass spectral data does satisfy the condition then the first mass spectral data is stored, recorded or prioritized. If it is determined that the first mass spectral data does not satisfy the condition then the first mass spectral data is discarded or downgraded. Scanning of the sample then continues at the first spatial resolution and further mass spectral data related to further pixel locations is acquired.