Neutral density filter
What is a neutral density filter
The moon is one of the most spectacular celestial objects. But the moon’s disk can be extremely bright. This glare washes out features on the moon’s surface.
A neutral density filter reduces brightness and improves contrast. It does this by limiting the amount of incoming light to a small portion. This
enhances the viewing experience giving you more detail on surface objects.
Reduced irradiation. This is the distortion at the boundary between light and dark areas. Manufactures use antireflection coatings on the glass of the filter to prevent ghosting.
Most decent telescopes come with a neutral density filter. But you may want to invest in a higher quality one If you plan on observing the moon frequently. A favorite is the Orion moon filter. High quality filters, the dimming transmitting percent ranges from 13% to 25%. Their anodized aluminum cells are threaded to be used with any standard telescope eyepiece.
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