Last year, I bought a Meade 10" SCT OTA, a 2" eyepiece and barlow, a cheap 2" diagonal, and a CG-5 Mount, off eBay in several different auctions. (Casino Winnings )
The problem I had was that no matter what I tried, I could not get the OTA cullimated. I thought that I got screwed on ebay.
Then the other day I got a new 10" Dob I ordered (More Casino Winnings ), and it happened to have a laser collimator in the box.
I was fooling around and put the laser cullimator in the SCT OTA. and noticed that the laser beam was not hitting the center of the Secondary Mirror, but near the mirror edge.
There is only one thing that can cause this.......the 90 degree diagonal was not a 90 degree diagonal. I estimated that the angle was more like 94 degrees!!!!!
I took off the back of the diagonal and the mirror was jacked up slighty on on side. I took out the mirror, scraped off the old glue, superglued the mirror back in the backing and reassembled the diagonal.
It now works and the SCT cullimates very easily.
I am posting this mainly to let people know that cheap telescope accessories (NO JUST TELESCOPES) may not work as well as we expect....."You get what you pay for!"
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