Author Topic: 10" f/20 Trischeifspeigler not working out well  (Read 45 times)

David Williams

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10" f/20 Trischeifspeigler not working out well
« on: December 27, 2017, 11:42:17 PM »
Since I posted queries re: 10" Chief design, my friend decided it was time to abandon and hand over his 10" f/20 trischeif project to me, as he was not able to get some aberrations to adjust out. He said the astigmatism responded ok, but there was "something else" showing up.

I've seen a few different formulas out there, Brucesdad accidentally posted a trischeif file which was eerily psychic of him. I'll have this scope soon, and there are diagrams for the spacing and tilt, so I'll be able to review the design, which seems to basically work. I suspect the formula is Buchroeder's f/20. The one in Rutten and vanVanrooij is f/14.7. I do have D. Groski's 8f20 OSLO file which I scaled to 10", but I'll access "spiderless" as I proceed.

I was told I'll have trouble dismounting the mirrors which were heavily siliconed to wooden cell parts, so> I'll bet there's the problem. I've mounted mirrors with dabs of silicone on good plywood before, but once I added a 4th central dot, and the changes in the wood distorted the mirror terribly. He said a Sawzall didn't work. Yeesh!

What have I gotten myself into?  At very least there will be a primary mirror which may be useful in other aps if it's of the expected quality. Gosh, a 10" f/12 Chief?Attached Thumbnails