Memo to Observers
June 7, 2004 
See:
Observing Support: 2.7 m Telescope
Instruments
Cassegrain f/8.8 Ritchey-Chretien focus
- IGRINS (currently at Gemini South)
- (DIAFI
- George and Cynthia Mitchell Spectrograph (GCMS) / VIRUS-P
Coudé f/32.5 focus
Robert G. Tull Coudé Spectrographs
- Cross-Dispersed Echelle Spectrograph (TS2) - Two foci available
Optical
| Primary Mirror | |
| Diameter | 2.72 m (107") |
| Focal length | 10.68 m (35') |
| F-ratio | 3.93 |
| Cassegrain f/8.8 Ritchey-Chretien focus |
|
| Focal length | 23.91 m (78.4') |
| F-ratio | 8.8 |
| Field of view | 61.5 arcmin |
| Plate scale | 8.62 arcsec/mm |
| Cassegrain f/17.7 focus | |
| Focal length | 47.98 m (157.4') |
| F-ratio | 17.65 |
| Field of view | 31 arcmin |
| Plate scale | 4.29 arcsec/mm |
| Coudé f/32.5 focus | |
| Focal length | 88.43 m (290.1') |
| F-ratio | 32.54 |
| Field of view | 6 arcmin |
| Plate scale | 2.32 arcsec/mm |
Mechanical
| Primary Mirror | |
| Weight | 3540 kg (7800 lbs) |
| Thickness | 31.8 cm (12.5") |
| Material | fused silica |
| Telescope Tube | |
| Diameter | 3.66 m (12') |
| Length | 9.75 m (32') |
| Telescope | |
| Weight | 145 t (190 tons) |
| Bearings | |
| Polar axis | pressurized oil and radial thrust bearings |
| Dec axis | preloaded ball bearings |
| Dome | |
| Diameter | 23 m (76') |
| Weight | 200 t (220 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 |
