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Mount John University Observatory (MJUO)


Latitude and longitude: -43:59:08, 170:27:54E (-43.98557, 170.46503)
Elevation: 3376ft (1029m)
Site manager: Frost
Internet access: high speed fiber
Weather statistics: 20% photometric, 40% useable, 40% cloudy
Typical good seasons:

Optical Craftsman 0.61m Telescope (OC61)

Type: Cassegrain
Aperture: 24in (61cm)
Focal length: 9020mm
F-ratio: 14.8
Focuser: electric secondary plus FLI

Type: fork
Pointing accuracy: 1arcmin
Maximum unguided tracking: >5min
Restrictions, if any: airmass less than 2
Computer: Linux + Windows
Software: TheSky, MaxIm DL, ACP, ACP Scheduler
Telecope Advocate: A. Henden

Typical seeing: 1.5arcsec
Best seeing: 1arcsec
Scattered light:
Image defects:

Camera: FLI PL09000
Filter wheel: FLI 5 slot
Filters: BVgri
Exposure ratios/filter:3.5:1.6:1.8:1.0:1.1
Pixel count: 1528x1528 (after 2x2 bin)
Pixel scale: 0.549arcsec/pix
Field of view: 14x14arcmin
Linearity (graph)
Full well: 65K ADU
Cosmetic defects:
Dark current:
Read time: 5sec
Shortest exposure: 0.2sec (iris shutter)
Compressed image size: 2.5MB
QE response (graph)

Typical Use of System
Deep imaging

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