Keep an Eye On Magnification
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Keep an Eye On Magnification
It may be tempting, if you're just starting to get into astronomy, to find the eyepiece with the most amount of magnification and attach it to your telescope. However, the aperture size of your telescope will set a limit to the amount of detail you can see on an object. Once you reach this limit, increasing the magnification won't help you see anything more.
For instance, if you have a 100 mm telescope, you would be able to see a little over 1 second of arc in detail or 1/3600 of a degree. A normal human eye can see 1 minute of arc of detail, or 1/60 of a degree. Theoretically, then, you would only need a magnification of 60 times to see the detail in a 100 mm telescope. However, since not everyone has perfect vision, magnifying 180 to 240 times would be sufficient to show the detail in a 100 mm telescope.
The best way to think of the maximum high-power limit you'll need, is to take the aperture size in mm and multiply by two (100 mm x 2 = 200 times) or take the aperture size in inches and multiply by 50.
| Guru Spotlight |
| Jerry Mayo |
