The Asiago Faint Object Spectrograph and Camera (AFOSC) is a focal reducer type spectrograph/camera twin of DFOSC, the instrument installed at Danish 1.54 m telescope at la Silla. It is installed at the Cassegrain focus of the Copernico 1.82m telescope. This enables imaging, spectroscopy (resolution from 240 up to 3600) and polarimetry to be performed.

From 2015 the instrument is equipped with Andor iKon-L936 BEX2-DD-9HF (detector: E2V CCD42-40 back illuminated CCD 2048×2048 active pixels; 13.5 μm each; technical details of the new chip are given in AFOSC technical report n. 25 from here) which turned out to be very similar, in terms of QE and physical dimensions to the previous CCD (technical report n. 21).

AFOSC technical data

  • Collimator focal length 234.27 mm

  • Collimator Linear Field 52.9x52.9 mm2

  • Beam Diameter 27.4 mm

  • Camera Focal Length 159.35 mm

  • Camera Linear Field 24.58x24.58 mm2

  • Reduction Ratio 0.68

  • Input f-number f/8.97

  • Output f-number F/6.10

  • Input scale 12.64”/mm

  • Output scale 18.59”/mm

  • Field of view 8.85’x8.85'

  • CCD Pixel scale 0.26”/pixel

  • Wavelength Coverage 330 - 1100 nm

  • Limiting Spectral Resolution 7350

AFOSC user manual (PDF)

Extinction curve for Ekar (txt file)

AFOSC comparison spectral Atlas (PDF)

credit: S. Dalle Ave