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We image spatial distribution of xenon ions in the focus of a laser beam of ultrashort, intense pulses in all three dimensions, with a resolution of three by twelve microns in the two transverse directions. This allows for studying ionization processes without spatially averaging ion yields. Our in situ ion imaging is also useful to analyze focal intensity proﬁles and to investigate the transverse modal purity of tightly focused beams of complex light. As an example, the intensity proﬁle of a Hermite-Gaussian beam mode HG recorded with ions is found to be in good agreement with optical images.