Schmidt 67/92 Telescope


The 67/92-cm Schmidt telescope, built in 1966, is located at Cima Ekar Observing Station close to the 182-cm telescope. It was moved from the original position at the Observatory site near Asiago in July 1991 to take advantage of the higher altitude and lower light pollution of Cima Ekar.

The building is not a traditional dome: the rotating part is of octagonal shape for easier mechanical assembling and was designed in part to test the proposed solution for the Telescopio Nazionale Galileo (TNG).

  • Correcting plate: 67 cm diameter in UBK7 Schott glass

  • Spherical mirror: 91 cm diameter in Duran-50 Schott glass

  • Focal length: 215 cm (f/3.2, scale 95.9 arcsec/mm).

Until 1998 the telescope was used with a photographic plate of 20 x 20 cm.

The corresponding field-of-view was 5.1 x 5.1 degrees.

The telescope is equipped with a 67 cm, 4.5 degrees angle UV-transparent objective prism, with a reciprocal dispersion at H gamma of 650 Ä/mm, and a 67 cm, 1 UV-transparent objective prism, with a reciprocal dispersion at H gamma of 1010 Ä/mm. The two prisms can be used in direct or reversed combination.

Recently (2017) the telescope has been considerably refurbished (new CCD camera, new filters, autoguider) and it can now be remotely controlled.

Coordinates of the S67 central pillar:


  • ON-Semi KAF-16803 (active area: 4096×4096 pixels, prescan: 30 pixels)

  • CCD scale: 0.87 arcsec/px (unbinned);

  • Pixel size: 9 μm

  • FOV: 59 x 59 arcmin

  • Full well capacity: 100 ke-

  • Dark current: 0.01 e-/pixel/sec at -30°C

  • A/D Converter: 16 bits

  • A/D Gain: 1.6 e-/ADU

  • Readout noise: 10 e-

  • Full frame readout time: 22 sec

  • Multistage Peltier cooler (max ΔT -60°C from the CCD heatsink temperature

  • Filters wheel with B and V Johnson-Bessel, u g r i Sloan filters; it is possible to work without filter as well

  • Minimum exposure time with electromechanical shutter: 0.2 sec


  • Sony IMX-174M (active area: 1920 × 1200 pixels)

  • CCD scale: 0.56 arcsec/pixel (unbinned)

  • Pixel size: 5.87 μm

  • FOV: 18 x 11.2 arcmin

  • The camera is mounted on a linear positioner that permits to adjust the focus independently from the main CCD camera focus

  • Minimum exposure time: 50 μsec

SCHMIDT USER MANUAL (september 2017) (PDF)


Variable stars in two open clusters within the Kepler/K2-Campaign-0 field: M35 and NGC 2158

Variable stars in one open cluster within the Kepler/K2-Campaign-5 field: M 67 (NGC 2682)

A PSF-based approach to Kepler/K2 data - I. Variability within the K2 Campaign 0 star clusters M 35 and NGC 2158

A PSF-based approach to Kepler/K2 data - II. Exoplanet candidates inPraesepe (M 44)

A PSF-based approach to Kepler/K2 data - III. Search for exoplanets andvariable stars within the open cluster M 67 (NGC 2682)