Image acquisition is a prerequisite for photogrammetry. In close-range and especially in real- time applications, there is a trend to move from photographical recording to electronical image acquisition by means of CCD sensors. The main problem with these solid state semiconductor devices is still either a rather low resolution (2-D array sensors) or a long exposure time (line scanners). The performance figures currently achieved, and the pros and cons of the different scanning techniques and diversity of sensors used (full-frame CCDs vs. frame-transfer CCDs vs. interline-transfer CCDs) are discussed.