A charged particle imaging apparatus comprising: A specimen holder, for holding a specimen; A particle-optical column, for: Producing a plurality of charged particle beams, by directing a progenitor charged particle beam onto an aperture plate having a corresponding plurality of apertures within a footprint of the progenitor beam; Directing said beams toward said specimen, wherein: Said aperture plate comprises a plurality of different zones, which comprise mutually different aperture patterns, arranged within said progenitor beam footprint; The particle-optical column comprises a selector device, located downstream of said aperture plate, for selecting a beam array from a chosen one of said zones to be directed onto the specimen.