The two EFOSC instruments have a long and successful history at La Silla. This page gives an outline, and will eventually have more details for interested historians of astronomical instrumentation.

EFOSC1 on the 3.6m Telescope

The first ESO Faint Object Spectrograph and Camera (EFOSC1) was at the ESO 3.6m telescope for over 10 years, until its replacement by EFOSC2 in October, 1997. Although conceptually a very simple instrument it could be used in eight different modes: direct imaging, long slit spectroscopy, slitless spectroscopy, echelle spectroscopy, imaging polarimetry, spectropolarimetry, coronography, and Multiple Object Spectroscopy (MOS). EFOSC1 was equipped with CCD #26, a Tek512 chip with 512x512 pixels of 27 micron size (scale is 0.61 arcsec/pixel).

EFOSC2 on the NTT

EFOSC2 was originally built at La Silla as the first light instrument for the NTT (in 1989), before EMMI (the ESO Multi-Mode Instrument) was ready. It was based on the reliable and versatile original EFOSC, but with a few improvements (e.g. a better CCD). With the arrival of EMMI, EFOSC2 moved to the 2.2m.

EFOSC2 on the 2.2m Telescope

EFOSC2 on the 3.6m Telescope

EFOSC2 was transferred to the 3.6m during period 60 (December 1997) to replace the original EFOSC.

EFOSC2 on the NTT (again)

EFOSC2 was transferred to the NTT at the start of period 81 (April 2008), replacing EMMI.