Contours for different BAF spectral type stars for which a Jupiter-, Saturn-, and Neptune-sized object can be detected at a S/N > 3.0 following a survey of 20 min per night for 152 nights. For a higher spectral S/N, smaller objects can be detected. If the spectral resolution is too low, the spectral line can no longer be resolved. For an instrumental setup to the right of a contour, an exoplanet detection is feasible for photon-shot-noise-limited observations. The instrumental setup used for our observations of β Pictoris with UVES on the VLT is indicated by the scatter point.