I'm interested in observing the moon and planets, and maybe some nebulae and star clusters.
I have a pair of binoculars:
- Nikon OceanPro 7x50 binoculars (around \$300)
- Celestron 20x80 binoculars (around $100)
The only reason I'm considering a spotting scope is that it has a magnification of 22-66x, compared to the binoculars' 25x. But I want to check if such high magnifications really work for astronomy.
Let's say I'm observing the full moon. What's the highest usable magnification, without resulting in too dim an image?
An Amazon review says that:
I have found that while the readability improves from 22x to about 38x the resolution actually decreases after that and I never use it from 40-66x, there is no point. Maybe it would have been better to have optimised it for 22-40x.
If the scope is limited to 40x in daytime use, I expect it to be worse at night, even observing the full moon.
I'm considering buying the scope only for the increased magnification over the binoculars, but if I end up using the scope only at 22x, it defeats the point of buying the scope in the first place. Should I stick with the binoculars?