Elliot 24-inch Telescope


The Elliot 24-inch telescope is located in the large white offset dome near the parking lot. It was installed in 2017.

Mount Bisque Taurus 600 equatorial fork mount
Pointing Accuracy 18.7 arcseconds RMS
Max exposure Unguided 5 minutes, Guided 60+ minutes
Telescope Planewave 24-inch CDK f/6.5
Focal length F=3962mm
Instrument Port #1 FLI PL16803 CCD - 9um px - 4096x4096 pixels / Filters=Clear, g', r', i', z', u', R
Instrument Port #2 55 mm TeleVue Plossl eyepiece
Instrument Port #3 Lhires III spectrograph - Ne calibration lamp - gratings=150g/mm, 300, 600, 1200 and 2400 - QSI 683 CCD. Slit camera FOV ~5'.
Instrument Port #4 Andor Ixon 888 frame transfer CCD, 13um px, 1024x1024px, 11.5' FOV
Autoguider Off-axis, ZWO ASI290MM Mini camera on Celestron 80mm f/11.4 refractor


The Lhires III PF0001 spectrograph is made by Shelyak Instruments. Specifications given below are accurate for the PF0001.

Spectrograph Specs slit width in arc seconds=1.35" slit width at focal plain=29um +/-1um      
Grating 150 300 600 1200 2400
Spectral domain or FOV in Å 2300 1140 550 250 85
Power of resolution 700 1400 2800 5900 175342
Limiting magnitude S/N=100 11 10.4 7 6.3 5
Dispersion (Å/pix) @ Halpha 3 1.4937 0.7 0.3 0.1
Dispersion (km/s) 150 75 35 17 5
0-order line   ~1.5mm  1mm  ~2mm 1.2mm
Micrometer cheat sheet     PDF PDF PDF
User verified positions   6450 @ 3.500mm     ~6563Å @ ~17.7mm

Wallace 24-inch Telescope

The 24-in telescope at Wallace is an Ealing "24-in Research Cassegrain Coudé" reflector on an asymmetric German equatorial mount. The optical specifications are as follows: D=600.075mm, F=9360mm, f/15.6, as measured after the recent refurbishment in 2009. The image scale is 22.04 arcsec/mm at its Cassegrain focus. The 24-in telescope was built as the centerpiece of the observatory in 1971. In its Cassegrain configuration it's been the telescope most used for research at Wallace and several papers and theses have been published using data obtained with it. The mirror was recoated in 2009 and the control system was redone in 2013 by Tim Brothers and Dan Gray of Sidereal Technology ("SiTech").


Mount Ealing Corporation
Pointing Accuracy 1.9 arcminutes RMS
Max exposure Unguided 120s - Guided 2-10min
Telescope Ealing 24-inch Cassegrain
Diameter of primary D=600.075mm
Focal length - f/# F=9360mm, f/15.6
Instrument Port #1 Eyepiece: 23mm - 40mm
Instrument Port #2  
Instrument Port #3; SBIG STL-1001e with Clear, BVRI filters
Instrument Port #4  
Autoguider Yes, External

The Shed Telescopes

There are four 14-inch telescopes (Celestron "orange tube" C-14's) in the Shed. One is mounted on a manual equatorial fork mount, the other three are mounted on robotic German equatorial mounts. All four have idential detectors and filter sets.  The roll-off roof building, affectionately refered to as "the Shed," was built in 1984.  The original four "orange tube" C-14's still reside in the Shed today.  They were refurbished in ~2016 and still produce excellent images and science data. 

  Pier 1 Pier 2 Pier 3 Pier 4
Mount Original Celestron equatorial fork mount driven by Byers retrofit Software Bisque       Paramount ME       Software Bisque Paramount ME with MKS5000 Upgrade Software Bisque  Paramount MEII  
Telescope Celestron C-14 Celestron C-14 Celestron C-14 Celestron C-14
Focal length - f/# F=~3910mm - f/11 F=~3910mm - f/11 F=~3910mm - f/11 F=~3910mm - f/11
Plate Scale 1.19"/px 1.26"/px 1.179"/px 1.25"/px
Camera SBIG STL-1001e CCD FLI ML1001 CCD  FLI ML1001 CCD SBIG STL-1001e CCD  
Camera info 1024x1024 pixels @24um 1024x1024 pixels @24um 1024x1024 pixels @24um 1024x1024 pixels @24um
Filter set ND 1.6 (2.5%T) for lunar observations, u', g', r', i', z', Clear, R Clear, u', g', r', i', z', R Clear, u', g', r', i', z', R Open, u', g', r', i', z', Clear, R
Autoguider N/A No Yes, off-axis No

Clear Skies!

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