IRCS Echelle Spectroscopy Overhead and Total Observing Time Calculator

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Exposure time for single shot (sec)

COADDS for single frame
For sky subtraction, we recommand the ExpTime*COADDS value less than 200 s for H-band and 300 s for K-band.

Observation Mode

Exposure time for Slit-Viewer (sec)
Observation sequence : (ABBA) SV-A-SV-B-B-SV-A-SV, (OSO) SV-Obj-SV-Sky-SV-Obj-SV, (OSSO) SV-Obj-SV-Sky-Sky-SV-Obj-SV .

Number of dummyread

* Additional overheads should be thought....
+ Setup Field (target acquisition) per each target : 10-15 min,
+ Telescope Pointing time : 1 min for dAZ = 30 degree,
+ Focus Adjustment (usually 3 times per a night) : 10 min per one time,
+ If you use AO188, for AO188 parameter adjustment : ~ 15 min per each target,
+ Filter change : less than 1 min.

Programmed by Tae-Soo Pyo, 2009. Feb. 6