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Good day folks. My Grandson would like to start using this Telescope Celestron Nexstar GT102, has been in the basement for years, and unfortunately, we appear to have misplaced the eyepieces.
Just wondering if anyone had any insight what would be a reasonable eyepiece for me to buy so he can see the moon at the very least decently enough.
Also, would Amazon be a good start for eyepieces that way I can get them fairly cheap and quick.
Thanks in advance
The manual says the original eyepieces had 1¼ inch barrels and focal lengths of 25 mm, 20 mm, 12.5 mm, 8 mm (all reasonable) and 4 mm (not so much). If I had to pick two replacements for a beginner, I'd get a 25 mm and a 10 mm. You can probably get an entry-level Plössl by Meade, Celestron, or Orion for US \$20-25 from the Cloudy Nights classifieds or \$30-40 new.
For the moon, you would normally not need a very high power eyepiece. 20mm would seem sufficient, on a telescope with a focal ratio of f/9.8. As this is a refracting telescope, if you get too much magnification you end up just magnifying the chromatic aberration. Smaller numbers mean more magnification.
Planets would require more magnification, on the other hand, fuzzy deep sky objects are easier to see with lower levels of magnification.
Amazon or any other major online retailer would be fine.
All the reviews say that this is a nice, easy to use telescope, but not that the tripod is rather lightweight and shaky. If that is an issue, you might try adding weight to it to the tripod to stabilise it.
