ESO ETCs & Simulations

Exposure Time Calculators (ETCs) play an important role in the overall process of ESO science operations. They are intended to give astronomers the ability to predict the signal to noise achieved under a set of assumptions about the performance of an instrument and the observing conditions. The accuracy of these predictions will improve as the instrument is calibrated and tracked under actual operational conditions. For the moment, ETC accuracy is dependent on preliminary calibrations and estimates of operational conditions. Users are advised to exert caution in the interpretation of the results and to report any result which may appear inconsistent.

Documentation

General descriptions for optical, infrared, UVES and VIMOS instruments.
Performance statement, Frequently Asked Questions.
Formula Book for signal and noise estimates.
Characteristic curves for the various optical components.

Exposure Time Calculators & Simulations

	Observation Domain
Location	Optical		Infrared
Location	Imaging	Spectroscopy	Imaging	Spectroscopy
La Silla	EMMI EFOSC2 SUSI 2p2 WFI	EMMI EFOSC2 HARPS FEROS	SOFI	SOFI
Paranal UT1	FORS2 FORS(P83+)	FORS2 FORS(P83+)	ISAAC SW LW	CRIRES ISAAC SW LW
Paranal UT2	FORS1	UVES FLAMES+UVES GIRAFFE FORS1
Paranal UT3	VIMOS	VIMOS MOS IFU	VISIR	VISIR
Paranal UT4			NACO HAWK-I	NACO SINFONI
VLTI Calculators	VisCalc CalVin

Notes

Released 28/08/2008: New ETCs for the "merged" FORS instrument. They are labelled "FORS(P83+)" in the table above.

Released 01/09/2008: Updated HAWK-I ETC.

Release Plan
Optical Imaging	Released 3.2.7 on 28/08/2008
Optical Spectroscopy	Released 3.2.7 on 28/08/2008
Infrared Imaging (SW, LW)	Released 3.2.1 on 30/08/2007
Infrared Spectroscopy (SW, LW)	Released 3.2.1 on 30/08/2007
Echelle Spectroscopy	Released 3.2.6 on 20/06/2008
Infrared Adaptive Optics	Released 3.1.0 on 25/07/2006 (VISIR spectroscopy) Released 3.2.6 on 20/06/2008 (SINFONI, NACO, CRIRES)
VLTI Calculators	Released 4.1.1 on 20/05/2008 (VisCalc) Released 2.0.3 on 20/06/2008 (CalVin)