Just the facts…

Meade Classic 10″ LX200 SCT

lx200 telescope
The blue scope is a Meade Classic 10″ LX200

The specifications of the Meade Classic 10″ LX200 are:

  • Optical Design – Schmidt-Cassegrain Catadioptric
  • Clear Aperture – 254mm (10″)
  • Focal Length – 1600mm (63″)
  • Focal Ratio – f/6.3
  • Resolution – 0.45 arc sec
  • Limiting Visual Magnitude – 14.5
  • Limiting Photographic Magnitude – 17.0
  • Secondary Obstruction – 4.0″ (16.0%)
  • Focuser – Moonlite CSL 2.5″ Large Format Crayford SCT/RC Focuser, motorized.
  • Weight – 35 lbs (OTA only, does not include fork, does include focuser)

Coronado SolarMax 90 Telescope

solarmax 90
This is the Coronado SolarMax 90 Telescope.

The specifications of the Coronado SolarMax 90 are:

  • Optical Design – Refracting Telescope
  • Clear Aperture – 90mm (3.54″)
  • Focal Length – 800mm (31.5″)
  • Focal Ratio – f/8.8
  • Bandwidth – < 0.7Å
  • Thermal Stability – 0.005 Å/°C
  • Blocking – Full blocking > 10e-5 from EUV to far IR
  • Focuser – Moonlite Large Format Crayford Refractor Focuser, motorized.
  • Weight – 28 lbs including focuser

Vixen ED103S Refractor Telescope


vixen ed103es refractor
Vixen ED103ES Refractor Telescope

The specifications of the Vixen ED103S are:

  • Optical Design – ED Apochromatic Refractor
  • Clear Aperture – 103 mm (4″)
  • Focal Length – 795 mm (31.3″)
  • Focal Ratio – f/7.7
  • Resolution – 1.13 arc sec
  • Limiting Visual Magnitude – 11.8
  • Limiting Photographic Magnitude – 14.3
  • Focuser – Moonlite Large Format Crayford Refractor Focuser, motorized.
  • Weight – 13.1 lbs including focuser

Orion ShortTube 80mm Guide Refractor

orion guide scope
Orion ShortTube 80 Guide Telescope

The specifications of the Orion ShortTube 80mm guide refractor are:

  • Optical Design – Refractor
  • Clear Aperture – 80 mm (3.15″)
  • Focal Length – 400 mm (15.75″)
  • Focal Ratio – f/5.0
  • Resolution – 1.45 arc sec
  • Limiting Visual Magnitude – 9.7
  • Limiting Photographic Magnitude – 12.2
  • Focuser – Moonlite Crayford Refractor Focuser, motorized.
  • Weight – 7 lbs including focuser

Stellarvue 50mm Finder Scope

50mm guide scope
Stellarvue 50mm guide scope.

The specifications of the Stellarvue 50mm finder refractor are:

  • Optical Design – Refractor
  • Clear Aperture – 50 mm (1.97″)
  • Focal Length – 200 mm (7.87″)
  • Focal Ratio – f/4.0
  • FOV – 5.75 degrees
  • Weight – 19 oz

How do we use them?

We have a wide array of telescopes at OOO.  Why do we have so many?  In planning the design of the observatory and reviewing the objectives, we decided it was never our intent to just do one thing, say deep sky astrophotography.  We always felt it would be better to be broad across a number of categories and perhaps not as deep on any specific one.  This would allow us to give students a very broad exposure to a number of topics.

With this in mind, we have a fine instrument for doing detailed spectrographic work with our 10″ LX200.  The LX200 is an older SCT design.  This telescope works ok when it is aligned perfect but SCT telescopes of this generation have some issues when it comes to astrophotography.  They suffer from coma, where the sharpness of the field of view is not the same across the entire frame.  This causes stars around the edge of a photograph to not be as sharp as those in the center.  In addition, they suffer from “mirror flop” in that the main focusing method of these telescopes is to push/pull the main mirror in the back.  This mechanical assembly suffers from having the mirror shift slightly when the telescope crosses the meridian (high point).  By using the LX200 for spectographic work issues like coma are not a problem as the object in the central FOV is only thing we are concerned with.  We can lock the mirror in place close to the main focus position using a simple set screw and then use the Moonlight motorized focus on the back of the scope to achieve final focus.  Finally, spectographic work requires the best light collection possible in order to image a spectrum in a reasonable amount of time.  The LX200 is the perfect scope for that task.

We are deeply indebted to Edd Weninger for loaning OOO the use of his Coronado 90mm SolarMax Solar Telescope.  This is one of the finest instruments I’ve ever had the pleasure of using.  Edd lives up in Overgaard, very close to our residence.  He has a fine personal observatory himself.  In loaning us the Coronado we can show students the amazing sights to be seen of our own sun.  The main background picture of the website was taken over memorial day of 2014 using the Coronado and the Skyris 274M camera.

The Vixen was purchased to provide a dedicated telescope for standard astrophotography.  There are some details to work out as to how well this will work as the scope is off axis and mounted on the side of the LX200.  I believe we should be able to use this within the limits of the scope.  Given the limited aperture of the scope, we are not looking to do very faint objects but there should be a reasonable number of objects within the grasp of this scope to do what we are looking to accomplish.

Finally that leaves us with our little Orion ShortTube.  This scope is the main guide scope that will work with the Vixen when it is doing astrophotography or it can work with the LX200 should we decide to do astrophotography with that instrument.  Either way, this little scope coupled with it’s StarShooter CCD camera is a favorite among many for guiding telescopes.  It should work fine for our needs.

Oh… and our little 50mm Stellarvue?  Well you always need a finder scope every now and then.  It would be foolish not to have one attached.

So what do all of these scopes look like mounted up?

collection of all of the scopes.
Here is the business end of the gang.

The Vixen has an Alnitak Flip-Flat covering the end of the scope.  This is used as both a dust cover and for taking dark and flat field images.  The red scope is the Coronado and the small open tube black to the middle right is the Orion ShortTube.  The big-boy LX200 is the large central scope.

many wires
Lots of wires!

When you want to run an observatory under remote control it takes a lot of wires to control the focus, the cameras, and all of the accessory items.  There are quite a few once everything is all included plus being sure to add a spare or two.  Running all of these wires is a bit of a chore.  You want few spares so you don’t have to tear things up just in case something breaks.


left side
View on the left.

Here is a view from the left showing the LX200 and the Coronado with the little Stellarvue just underneath.

right view
View from the right.

Here you can make out both the Vixen and the LX200.

guide close up
Here is the Orion guide scope close up.

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