Enjoy the writeup.
ScopeScavenger 12" Truss Prototype 1.0
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Posted 03 January 2014 - 01:03 AM
Posted 03 January 2014 - 07:26 AM
Posted 03 January 2014 - 10:31 AM
Posted 03 January 2014 - 10:41 AM
Posted 03 January 2014 - 12:40 PM
Posted 03 January 2014 - 05:46 PM
Your scope looks great, you used a lot of interesting ideas in this build.
I would be curious to learn how well is the mirror cell working and what mirror thickness is in the scope.
I always thought a whiffle tree primary mirror cell would be needed for mirrors like yours based on PLOP calculations.
Posted 03 January 2014 - 06:09 PM
Posted 04 January 2014 - 01:51 AM
Posted 04 January 2014 - 08:48 AM
Posted 04 January 2014 - 02:27 PM
If your mirror is thin (all modern production mirrors are) you'll see cell induced astigmatism with improper cell design. PLOP helps you design a support system that equalizes and distributes evenly the support forces on the mirror back. Imagine for a second that your plywood back is a little warped, not enough to notice with the naked eye but enough to have a high spot. It's true that the soft backing will make this impossible to feel with your hand but the support force will be higher in that area (as applied to the back of your mirror) . It doesn't take much force difference to warp a mirror that's 12" diameter and 1.5" thick.
I knew when building this the mirror cell would be the most debated issue. What real world difference does a multipoint floating cell make? Will i only notice it under certain conditions? Will it make a visual observation difference?
Posted 05 January 2014 - 12:40 AM
Posted 14 January 2014 - 12:51 AM
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