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Cerro Tololo International Observatory (CTIO)


Latitude and longitude: -30:10:20 , 70:48:00W
Elevation: 2100m
Site manager: CTIO

Internet access: T1

Weather statistics: 60% photometric, 30% usable 10% cloudy
Typical good seasons: Spring, Summer, Fall



Type: Corrected Newtonian
Aperture: 20cm
Focal length: 720mm
F-ratio: 3.6
Focuser: OKI electronic

Paramount ME
pointing accuracy: 1arcmin
maximum unguided tracking
restrictions, if any: 5arcmin
Computer: Linux
Software: TheSky, MaxIm DL, ACP, ACP Scheduler
Telecope Advocate: A. Henden

Typical seeing: 1-2arcsec
Best seeing: subarcsec
Vignetting: severe; 30%
Scattered light: some, corrected during processing
Image defects: some column defects

Type: Apogee U16m
Filter wheel: Apogee 7s
Filters: BVugriz
Exposure ratios/filter:
Pixel count: 4096x4096
Pixel scale: 2.6arcsec/pix
Field of view: 2.9x2.9 degrees
Linearity (graph)
Full well:
Cosmetic defects: some column defects
Dark current:
Read time:
Shortest exposure: 0.2sec (3sec recommended)
Compressed image size: 10MB
QE response (graph)
Images of typical darks, typical flats

Typical use of system 
APASS survey during dark time; some time currently available for other projects during bright time.

Miscellaneous notes

AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484