Memo to Observers
June 7, 2004 —
pdf
Instruments
|
Cassegrain f/8.8
Ritchey-Chretien focus
|
CCD WHT Camera
Imaging Grism Instrument (IGI)
|
Cassegrain f/17.7 focus
|
Large Cass Spectrometer (LCS)
LCS-Spectropolarimeter (SPol)
Photometer (P45)
|
Coudé f/32.5 focus
|
Coudé Spectrometer (cs1)
- Two foci available
Cross-Dispersed Echelle Spectrometer (cs2)
- Two foci available
|
TCS
|
107" TCS Manual
107" TCS Quick Start
107" TCS Troubleshooting
|
Cautions
|
2.7m Cautions
|
Optical
|
Primary Mirror
|
diameter:
|
2.72m (107")
|
focal length:
|
10.68m (35')
|
f-ratio:
|
3.93
|
Cassegrain f/8.8
Ritchey-Chretien focus
|
focal length:
|
23.91m (78.4')
|
f-ratio:
|
8.8
|
field angle:
|
61.5 arcmin
|
plate scale:
|
8.62 arcsec/mm
|
Cassegrain f/17.7 focus
|
focal length:
|
47.98m (157.4')
|
f-ratio:
|
17.65
|
field angle:
|
31 arcmin
|
plate scale:
|
4.29 arcsec/mm
|
Coudé f/32.5 focus
|
focal length:
|
88.43m (290.1')
|
f-ratio:
|
32.54
|
field angle:
|
3 arcmin
|
plate scale:
|
2.32 arcsec/mm
|
Mechanical
|
Primary Mirror
|
weight:
|
3540kg (7800 lbs)
|
thickness:
|
31.8cm (12.5")
|
material:
|
fused silica
|
Telescope Tube
|
diameter:
|
3.66m (12')
|
length:
|
9.75m (32')
|
Telescope
|
weight:
|
145t (190 tons)
|
Bearings
|
polar axis:
|
pressurized oil and radial thrust bearings
|
dec axis:
|
preloaded ball bearings
|
Dome
|
diameter:
|
23m (76')
|
weight:
|
395t (435 tons)
|
Historical
|
Construction
|
started:
|
April 1966
|
completed:
|
October 1968
|
Contractor
|
design:
|
Charles Jones, Inc.
|
telescope:
|
Westinghouse
|
dome:
|
C.H. Lovell Construction Co.
|
optics:
|
Davidson Optronics
|
