Angled Secondary?Posted By Karl Kirk |
Please excuse my ignorance... I'm curious...
Is it feasible to have an angled secondary mirror on a newtonian, instead of the traditional perpendicular 90 degrees, with acceptable results at the eyepiece?
For example, a 20" mirror with a 77.5" distance to a secondary angled at 45 degrees, to an "offset" focuser also angled at 45 degrees, 4" off to the side of "middle" structure.. and 14" off the axis? ( Which, I think, comes out to an F/4.8 scope with the eyepiece at 5' 8" height at zenith above the mirror? And also would bring in the center of gravity towards the base? )
Since I've doodled this out, if it *is* feasible then someone's probably already done this... are there examples of such in existence, and I suppose there's a name for such a critter?
Thanks in advance!
Is it feasible to have an angled secondary mirror on a newtonian, instead of the traditional perpendicular 90 degrees, with acceptable results at the eyepiece?
For example, a 20" mirror with a 77.5" distance to a secondary angled at 45 degrees, to an "offset" focuser also angled at 45 degrees, 4" off to the side of "middle" structure.. and 14" off the axis? ( Which, I think, comes out to an F/4.8 scope with the eyepiece at 5' 8" height at zenith above the mirror? And also would bring in the center of gravity towards the base? )
Since I've doodled this out, if it *is* feasible then someone's probably already done this... are there examples of such in existence, and I suppose there's a name for such a critter?
Thanks in advance!