VISTA: Exposure Time Calculator

Version 1.5   2009-11-30   (Release Notes)

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The VISTA/VIRCAM Instrument data used in the ETC are available as ascii files on request to the VISTA PI

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Input Flux Distribution

Power law:
    Temperature:   Kelvin
Single line:
    Wavelength:    nm (in the range [900.0-2500.0] nm)
    Flux:          ergs/s/cm2
    Width:         nm 

Object Magnitude:  Vega:  Value:  (per square arcsec for extended sources)
                   AB:    Value:  
                   Flux:  Value:  (ergs/s/cm2)

Spatial Distribution:
       Aperture diameter:   arcsec 
    Point Source
    Extended Source

Instrument Setup


Sky Conditions

Brightness:         mag/arcsec2   [default dark sky: Z = 18.2 Y = 17.2 J = 16.0  H = 14.1  KS = 13.0  NB118 = 16.3] 
Seeing:             arcsec (value for the selected filer)
Extra Extinction:   mag/unit airmass [added to default Paranal clear night sky extinction]

Observing Setup

Detector on-chip integration (DIT):  seconds (Note, minimum possible is 1.0 second)
Object exposure time:    seconds
S/N Ratio:              
Observing Strategy:
    Exposure coadds (Ndit):       
    Exposure loops (Nexp):        
    Microstepping pattern (NxM):  
    Jitter pattern (Njitter):     
    Number of pointings (Npaw):    [normally, Npaw=1 for single pawprint, Npaw=6 for full tile]