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Ball Scope Ideas

Started by timo4352, 08/24/2008 10:53PM
Posted 08/24/2008 10:53PM Opening Post
Hi All
I'm finally getting ready to start an 8" ball scope project that I've been thinking of doing for a while now. There's not a lot of info or ideas on design out there that I have found. The Trackball has some good ideas for building a tracking mount - and the Sphere-o-scope written up on CN has good ideas for design. There's also one dubbed the cookie jar scope that has some good ideas. I know I'm going to use an acrylic lighting diffuser globe for the ball to save time building a sphere. Anybody have any additional ideas or past experience to share on building a ball type scope? Tracking mount ideas? Tracking would be a huge plus.
I've seen MAG1 is back in business but I could never afford the price - it's gotta be home built to keep the cost down.
Thanks in advance and looking foward to hearing your thoughts and ideas.

Attached Image:

timo4352's attachment for post 43413
Posted 08/30/2008 07:21PM | Edited 08/31/2008 12:30AM #1
I've run NEWT for the ball scope and come up with the following numbers:
Mirror dia 8"
Focal ratio 5.75
Secondary 1.52"
Tube ID 9" X .06 wall
2" focuser at 1.4 focuser height - Kineoptics HC2
Gives me .45" 100% illumination
and 1.0" 75% illumination
19% obstruction

It all looks good to me - but does anybody see anything I'm missing? I only want to build this thing once.