Observing Overheads

Telescope and dome

Telescope overheadsTime
Target acquisition (imaging)4 min (max)
Target acquisition (spectroscopy)6 min (max)
Instruments change (echelle – single – photometry)30 s


Ondřejov Echelle spectrograph (OES)

  • reading–out: 43 s
Standard calibration exposure times
OES ExposureTime
Flat25 s
Dome-flat700 s
Comp5 s

Single order spectrograph

  • reading–out: 19 s
Calibration exposures for different grating angles
Center of the lineGaia*CA IIHe IHγ
Flat15 s10 s10 s10 s5 s10 s40 s
Comp Th-Ar10 s10 s10 s10 s20 s40 s40 s
* ‘Gaia’ corresponds to wevelengths 8400-8870 Å
  • change of the grating position (maximum for any spectral region): 30 s

Photometric camera

  • reading–out (binning 1×1): 10 s
  • change of the photometric filters: 6 s
  • photometric offsets: few seconds (depending on value of offset)

For any further questions about the telescope, instruments performance, or observational overheads, please write us to email proposal@asu.cas.cz.