Millikin University - Decatur, IL
Equipment Page

Telescopes At Millikin:

Parallax Instruments 20" Ritchey-Chrétien

Telescopes Specifications:
Model No. 
 Clear Aperture
Focal Ratio 
 F/8.1 Focal Length 
Primary &
Mirror Substrate
 Zero Expansion

 2.70x  Spacing
Mirror Coatings   AISiO Optical Tube
Optical Tube Length
 56"  Optical Tube Weight  130lbs.
Focuser  2.7"  Finder Scope  7X50
Tube Rings
Standard  Primary
Cooling Fan 
Slewing Handle  Standard   Tube C'wt
Bar Assy. 

Meade LX 200 8" Schmidt-Cassegrain

Telescope Specifications:
Focal Length  1280mm  2000mm 
Aperture  203mm  203mm 
Secondary  88mm  76mm 
Obstruction  43%  37% 
Type  SCT SCT 
Drive  Fully Computer Controlled;
64359 Object Library;
Automatic GO TO Capability 
Altaz Yes   
Polar  Yes with optional wedge  
Eyepiece  26mm Plossl  
Finder  8x50  
RS232  Yes  
Power  18v DC (AC
adapter included)
Weight  41 lbs  41 lbs
Tripod  Standard  Standard

CCD Cameras At Millikin:

 CCD Kodack
+ TI TC-237 
 Pixel Array 765 x 510 pixels,
6.9 x 4.6 mm 
 Total Pixels 390,000  Pixel Size  9x9 microns 
Full Well Capacity (ABG)  `50,000 e-   Full Well Capacity (NABG)  ~100,000 e-
 Dark Current 1e-/pixel/sec at 0C  Antiblooming  KAF -0402ME is
NABG only ABG optional (KAF-0402LE) 
 Shutter Electromechanical  Exposure  0.11 to 36000 seconds,
10ms resolution 
 Correlated Double Sampling Yes A/D Converter  16 bits 
A/D Gain  2.6e-/ADU  Read Noise  15e-RMS 
 Binning Modes 1 x 1, 2 x 2, 3 x 3  Pixel Digitization Rate  Up to 420,000 pixels per second 
Full Frame Acquisition   ~35 seconds  Field of View 12 x 8 arcminutes on f/10 Meade LX 200 
 Pixel Size .9 x .9 arcseconds on f/10 Meade LX 200   Limiting Magnitude  Magnitude 14 in 1 second
(for 3 arcsec FWHM stars)  Magnitude 18 in 1 minute   Cooling Standard Single Stage Thermoelectric, Active Fan, Water Assistant Ready -45 C from Ambient Typical 
 Temperature Regulation +-0.1 C  Power  5 VDC at 1.5 amps, +-12 VDC at 0.5 amp desktop power supply included 
 Computer Interface Parallel Computer Compatibility  Windows 98/2000/Me/NT/XP 
 Guiding Dual CCD Self-Guiding 

Imaging CCD  Kodak Enhanced KAF-1001E  Pixel Array  1024 x 1024 pixels, 24.6 x 24.6 mm 
 Total Pixels 1.0 Million  Pixel Size  24 x 24 microns 
Full Well Capacity (NAGB)   200,000 e-  Dark Current 9 e-/pixel/second at 0 degrees C 
 Antiblooming NAGB only  Shutter  Electromechanical 
Exposure  0.12 to 3600 seconds, 10 ms resolution  Correlated Double Sampling  Yes 
A/D Gain  2.0e-/ADU  Read Noise  14.8e-RMS 
 Binning Modes 1 x 1, 2 x 2, 3 x 3  Full Frame Download  40.8 seconds 
Cooling - standard  Two Stages Thermoelectric, Water Assist, -40 C from Ambient Typical   Temperature Regulation  +-0.1 degrees C
Power  10-18VDC nominal, Universal AC to 12VDC desktop supply   Computer Interface Parallel 
 Computer Compatibility Windows 98/NT/2000/ME/XP/Mac OS-X 
 Guiding  Dual CCD Self-Guiding Standard

SGS-Self Guided Spectrograph

Dispersion:   Two grating available, on a carousel for rapid selection
150 lines per mm (4.3 angstroms per pixel)
600 lines per mm (1.0 angstroms per pixel)
 Slit width 100 microns wide entrance slit 
 Acceptance cone angle  F/6.3 by F/10
 Narrow slit & 600 lines/mm 2.4 angstroms 
Narrow slit & 150 lines/mm  10 angstroms 
 Wide Slit & 600 lines/mm 10 angstroms 
 Wide slit & 150 lines/mm 38 angstroms 
Relative Sensitivity to Diffuse Sources:   
Narrow Slit & 600 lines/mm  1.0 
Narrow slit & 150 lines/mm  4.0 
Wide slit & 600 lines/mm  4.0 
 Dispersion: 1.07 0r 4.3 angstroms per pixel 
Resolution  Emission line is recorded with 2.4, 10 or 38 Angstroms Full Width at Half Maximum 
 Spectral Coverage per frame About 750 Angstroms with the high resolution grating, or 32000 with the low resolution grating 
 Center Wavelength Selection  Calibrated Micrometer Adjustment
 Wavelength Range 3800 to 7500 Angstroms 
 Sensitivity  Signal to noise ration of 10:1 for a 9th mag star, 20 minute exposure using a non-AGB ST-7 and a 10 inch (25 cm) apertaur in high resolution mode. An ABG ST-7 will reach magnitude 8. The low resolution mode will be 1.5 magnitudes more sensitive.
 Entrance Slit  18 micron (2.3 arcseconds wide with 63 inch focal length telescope or 72 microns
 Uses:  Stellar Classification
Analysis of Nebular Lines
Identification of spectroscopic binaries
Measurement of stellar proper motion to +/- 6km/sec accuracy
Measurement of Emission Nebula Proper Motions
Spectra of laboratory and field sources

Millikin University - Decatur, IL
Millikin University - Decatur, IL