Capacitive proximity sensing is carried out by detecting a relative change in the capacitance of a scoop capacitor formed by a conductor and a surrounding ground plane. The pot comprises a first material, which has a first temperature expansion coefficient and the cover comprises a second material, which has a second temperature expansion coefficient. Initially, a first database is designated as a source database and a second database as a target database. Furthermore, the specular control device may prevent the specularly reflected light from reaching the spectroscopic analyzer. The sheave includes a groove around its outside diameter in which a sheave rope is placed.