Hi Bros, which focal ratio is better, i.e f/6, f/8, f/10 for refractor telescope?
Thanks
Finding a Telescope for beginner
- weixing
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Hi,
Slower focal ratio Refractor is usually easier to manufacture, so usually slower focal ratio Refractor telescope will perform better than a faster focal ratio Refractor telescope of the same class from the same manufacturer.
Have a nice day.
Slower focal ratio Refractor is usually easier to manufacture, so usually slower focal ratio Refractor telescope will perform better than a faster focal ratio Refractor telescope of the same class from the same manufacturer.
Have a nice day.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance."
Depends on your aperture. You wouldn't want to stretch the focal length of small aperture telescopes, that will affect your image quality. Also depends on what you wish to do with the scope. If you would want to consider astrophotography, a f6 scope will do. Larger focal ratio means longer focal length, and that will be frustrating especially if you don't have a tracking mount. Yes, lower f-ratio scopes are more costly, but there is no free lunch. Get something that will last instead of something that will end up in the second hand market real soon.