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Telescopes

The telescope is the most obvious component of a deep space imaging system, as it contains the mirror that is especially shaped for collecting deep space photons.   However, a general rule of thumb is that more of the expense should be invested in the mount than the telescope.  This is because rock solid tracking is very essential in order for even high end scopes to be functional.

There are generally two classes of telescopes: "main" scopes and "guider" scopes.   When the main scope is being used to take a long duration exposure, the imaging sensor can not be interrupted.   A second entire scope (with a second sensor operating with much higher sensitivity and a lot faster exposure) can be used to "guide" the main scope, to help ensure that a steady track is being maintained.    The key is really having the faster second sensor doing the "quick look" or "second opinion".  It is also possible to use OAG (On-Axis Guiding) where the main and guide scope are one and the same (but the guide camera is still separate).

Vixen VC200L

I started with a VMC200L by about a year later swapped it out to the VC200L.  The differences are subtle but significant for astrophotography.

VC200L info reference:  http://www.skybadger.net/equipment/telescopes/vc200l/

VMC200L comparison for reference:  (main difference is the corrector lenses in the baffle before the draw tube)

The VC200L is an 8" modified-SCT design.   For my VC200L, the spider vanes have been grinded down to be thinner.  We also use the Vixen Tube Rings to secure the tube to the V-style dovetails.  We replaced the stock Vixen dovetail with a longer 11" ADM V-style rail.   In addition to providing rigidity, the Vixen Tube Rings also support a second 11" ADM V-style rail at the top of the tube, which supports holding the ST80 guider scope.

We've also swapped the focuser from the stock R&P to a SI 2515HD focuser with MotorTouch.  An unfortunate consequence of the focuser was that the stock Vixen focal reducer could not be adapted. While SI claimed to have an endcap that would support the Vixen reducer, after waiting over a year it never materialized.   However, PreciseParts was able to produce the necessary adapter within a few weeks.   Then, unfortunately, the PreciseParts adapter no longer allowed the 48mm Light Pollution Suppression filter to be installed.   The solution for that was to order the clip-in version of the filter (which is Canon EOS specific) instead of using the 48mm screw-on version.

Vixen VC200L (1800mm FL, f/9): 

http://www.vixenoptics.com/Vixen-VC200L-Reflector-Telescope-p/2632.htm
http://www.chuckhawks.com/vixen_VC200L_telescope.htm
http://www.cloudynights.com/topic/424720-re-collimation-of-the-vixen-vmc200l-long/
http://www.threehillsobservatory.co.uk/astro/vixen_flr.htm


ES80 Triplet

The ES80 is a smaller more portable scope with a wider field of view.  It is intended to be used on the Celestron AVX mount.

Upgrades:  http://www.cloudynights.com/topic/530523-first-light-with-es-80ed-triplet-m42-sample/

ES80 Triplet (480mm FL, f/6):  http://explorescientificusa.com/products/80mm-apochromatic-refractor?variant=597773165

Off Axis Guider:  https://www.amazon.com/gp/product/B01B2OR8QG/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Orion ST80

Use as a guider camera.

 
Orion ST80  (guider, f/5): http://www.telescope.com/Telescopes/Refractor-Telescopes/Refractor-Optical-Tube-Assemblies/Orion-ShortTube-80-T-Refractor-Telescope/pc/1/c/10/sc/346/p/9946.uts

SBIG ST-i Kit

This is a 100mm f/2.8 Lense Kit, C-Mount.

https://www.sbig.com/products/cameras/specialty/st-i/st-i-guiding-kit/