I wanted to start using a green laser pointer (GLP) as a supplement to my 9 x 50 finderscope on my Orion XT8 telescope, but I didn't want to spend a lot of money or time on it, and I didn't want to deal with drilling any holes in my optical tube assembly (OTA). I wanted the GLP finder because while the 9 x 50 finderscope is great for zeroing in on a faint fuzzy once you are in the right area, getting to the right area can be a pain with a Dobsonian.
I was able to find a very inexpensive (less than $10) green laser pointer on Amazon. There are more expensive varieties out there, but I figured that at such a low price it wouldn't be the end of the world if it didn't work well. As it turns out, the inexpensive GLP has worked fine for a while now.
But how to mount it on my Orion XT8 telescope? I didn't want to spend money on a real mount, and I didn't want to deal with drilling holes in my telescope (I know it's not really that big of a deal but I just wanted to avoid it if possible). Inspired by the way Apple uses magnets to secure things like the iPad cover, I looked on Amazon and ordered a package of 50 1/4" x 1/10" Neodymium rare earth magnets for less than $10.
When the magnets arrived I confronted the fact that I still didn't have a plan for exactly how connect them to the GLP. After mulling over a few possibilities that I rejected because they felt like too much work, I hit on the idea of simply taping four of the magnets to a popsicle stick using black electricians tape, a pair at each end, and then rubber-banding the GLP to the opposite side of the popsicle stick, like so:
Then it was time for a test drive. I was apprehensive about how hard it would be to align the GLP, but I quickly discovered that it was pretty easy. Just click the GLP on the tube, look through my 9 x 50 right angle correct image (RACI) finderscope, wiggle the shining laser beam back and forth until I see it in the finderscope, and then put the beam more or less close to the crosshairs. Using this method it takes literally only about 2 seconds to align the GLP. For vertical (for lack of a better word) alignment of the beam I just wedge stuff as needed between the GLP and the popsicle stick.
I quickly became addicted to using the GLP. It makes it a breeze to get the telescope pointed to within a degree or two of the target, and from there I use the RACI finderscope to hone in on it. No more contorting myself to get to the right spot behind a red dot finder, and seeing where a big green laser beam is pointed on the sky is a lot easier than correctly placing the red dot on an inexpensive red dot finder.
When winter came along I found another advantage to a magnetic GLP mount: it makes it easy to keep the GLP warm. I discovered that my GLP quickly dims when it gets cold, so to keep it usable I keep it in my pocket (or when it is really cold inside my pants against my skin) until I need to use it. Then I click it on the tube, quickly align the beam using the RACI finderscope, use the beam to put the telescope on the target, and then pop the GLP off and put it back in my pocket.
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