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Telescope SCT OTA on GEM

Deforking the Meade LX50 8" SCT, and modifying the OTA (Optical Tube Assembly) for GEM use:

The goal is to convert the Meade LX50 telescope to be more manageable for transporting and handling.  So the original fork mount was detached from the OTA, and then a dovetail was attached to the OTA for GEM use.  Don't recall the exact details of removing the fork arm, since it's been several years - but it entails removing 6 screws (3 per side in a flattened triangle pattern) from the OTA.

The weight is now distributed in four ~12 lb. sections:
  • OTA
  • GEM
  • counterweights
  • tripod

The finished GEM conversion:

The OTA is mounted on an Orion Sky View Pro (SVP) EQ GEM tripod (non-tracking and non-GOTO), with ScopeRoller wheels.




Original Meade LX50 fork mount attached to the OTA - total weight: 36 lbs.!:

Without the 25 lb. fork arm assembly, the OTA weighs only 11 lbs. - making it much lighter and less bulky to handle.




Losmandy VSCT13 dovetail mount is bolted to the OTA - and secured with 10" diameter hose clamp rings:

Hose clamp rings are covered with 1/2" red heat shrink tubing to prevent tube scratching.  The large 10" diameter hose clamps were bought from a marine/boating store, since the largest clamps found at heating/air conditioning (HVAC) stores were only 7" in diameter.




Accessories attached to the OTA:

(from left to right)

  • Lumicon 200mm finder scope (w/diagonal and 25mm eyepiece)
  • BSA RD30 red dot pistol sight mounted on a 3/4" wide aluminum strip
  • black plastic shipping pallet tie-down strap is attached as a carrying handle
also ...
  • large focus dial attached to original focus knob
  • sawed off Walgreens plastic pill bottle used to keep dust out of diagonal when eyepiece is not installed (orange in color, barely showing)



Green laser pointer attached to a 1/2" wide aluminum U-channel that is bolted to the OTA:

A green laser will allow you to point at distant celestial objects in the night sky.  Care must be taken not to aim at people and aircraft.



Currently using a turn-key worm gear hose clamp (shown with a yellow key) to quickly secure and unmount the green laser pointer:

The hose clamp was bought from an auto parts store, and is covered with 1/4" red heat shrink tubing to prevent scratching the OTA.



Glow-in-the-dark (luminous / phosphorescent) sticker on each tripod leg:

Prevents observers from accidentally kicking the tripod leg at night.  eBay sticker seller claims that 15 minutes of light exposure should glow for about 10 hours - not radioactive.



Orion Nebula - M42

Taken by the author at Fremont Peak State Park, California. Circa 1997. Meade LX50 8" Schmidt-Cassegrain telescope, Olympus OM-1 camera body w/T-adapter, Lumicon Easy Guider w/f6.3 focal reducer, Lumicon Deep Sky filter. ~15 minute exposure with 100 ISO slide film. Scanned with Minolta Dimage Scan Elite II.

Click on the image to get a larger 1.1MB JPEG image.


The telescope at Rancho Canada del Oro (August 2013):

This park is open after dark only by special arrangement with SJAA and SCC OSA.
Clear Dark Sky chart:

http://cleardarksky.com/c/RCDOCAcsk.gif