Telescope: |
Mounting of telescope: | altitude-azimuth |
Total moving weight of telescope: | 43 tons |
Weight of telescope tube: | 6800 kg |
Type of optical system: | (Super) Ritchey-Chretien |
Equivalent focal distance of system: | 28160 mm |
Effective aperture ratio of system: | f/11 |
Position: |
Longitude: | 17° 52' 59.7" W = 1h 11m 32.0s W |
Longitude (new from GPS): | 17° 53' 06.3" W |
Latitude: | +28° 45' 20.5" |
Latitude (new from GPS): | +28° 45' 26.2" |
Altitude: | 2382 m |
Minimum accessible declination: | -55 deg. |
Primary mirror (M1): |
Second degree coefficient of radius: | -4.8828125 x 10^-5 |
Fourth degree coefficient of radius: | +1.721171778 x 10^-15 |
Sixth degree coefficient of radius: | -1.5207 x 10^-25 |
Mirror material: | Zerodur, delivered by Schott Glaswerke in Mainz, Germany |
Mirror: | Ground and polished at Tuorla Observatory, university of Turku, early spring 1988 |
Diameter: | 2560 mm |
Diameter of aperture stop: | 2495 mm |
Diameter of central hole: | 340mm |
Peripheral thickness: | 190.3mm |
Weight: | 1925 kg |
Focal Length: | 5120 mm |
Aperture ratio: | f/2 |
Conic constant: | -1.014785 |
Secondary mirror (M2): |
Diameter: | 510 mm |
Weight: | 35 kg |
Radius of curvature: | -2287.25 mm |
Conic constant: | -2.234127 |
Other: |
Min zenith distance due to zenith sigularity: | 4 arcmin |
Blind tracking accuracy: | 0.17 "/min at zenith distance 14° 0.6 "/min at zenith distance 70° |
Linear coefficient of thermal expansion of mirrors: | <0.00000001/K (between 0° and 50°C) |
Energy concentration: | 80% within 0.4" 100% within 0.7" |
Total field of view: | 30' |
Focal plane scale: | 7.33"/mm |
Focus-value scale (in telescope focal plane): | 66 focus units / mm shift   ( or 15.2 micron/unit) |
Focus-value scale (at secondary): | 0.35 micron movement per focus unit (a positive offset moves the secondary away from the primary) |
Autoguider X,Y probe scale: | 0.00718 arcsec per unit |
Autoguider TV pixel scale: | 0.222 arcsec in X and 0.145 arcsec in Y |