Lost vision The telescope was working fine until I was trying to match the view through the smaller spotting scope with that of the main telescope, and suddenly I could faintly tell I was aimed at the moon by a soft glow alone, but could no longer actually see details nor the usual brightness of it. I've taken the scope apart and cleaned the lenses and mirror. I can see beautifully if I remove the eyepiece, but of course I'm just looking at the mirrors inside at that point. When I replace the eyepiece, all I can see is that very faint glow which, when focused, gives me that funky view of the inside of my own eyeball like when you get your eyes checked at the optometrist's office and they shine that bright light in your pupil. Any idea what's happened here and how I can fix it? Maybe I need a new eyepiece?
Your telescope is a "Newtonian," as such it requires regular "collimation" Collimation the alignment of the optics. The mirrors must be lined up properly for the telescope to deliver a good image to the eyepiece. Your scope sound like it is way out of collimation. My guess is that the diagonal (secondary) mirror has rotated in it's mount. There are three basic tools for collimating a Newtonian the Sight Tube, Cheshire and Autocollimator. To get your digonal aligned correctly you need a sight tube. Rather than spend a lot on these consider making your own and keep an eye on eBay offerings. Don't bother investing in a laser collimator, they simply don't do the job unless you go for the very best. From some help with the collimation process check these links.
The 60 page pamphlet "New Perspectives on Newtonian Collimation," Fourth Edition by Vic Menard and Tippy D’Auria runs $10, but if you really want to do it right it's worth the money. HTH, George Read More At : Deep Space 78-9518 (675 x 114mm) Telescope...