Anonymous asked in Science & MathematicsAstronomy & Space · 1 decade ago

Do I need a "moon filter" for my telescope?

Will it hurt my eyes at night if I look at the moon through my telescope? The telescope says it doesn't come with a moon nor sun filter.

11 Answers

  • 1 decade ago
    Favorite Answer

    no you dont need a moon filter. but yes you need a sun filter to view the sun safely.

  • Anonymous
    5 years ago

    For the best answers, search on this site

    There are several different reasons. First, the Hubble telescope can't be directed to the moon because the instruments would be fried. The telescope is made to pick up very faint objects and something as bright as the moon would damage the detectors. Second, a telescope's sensitivity is determined by how large the mirror is. A larger mirror can distinguish smaller angular separations. Now, even though the things left on the moon are large, the moon is far away, so those things look very small. Remember that the Hubble telescope is not that far above the earth, so it really isn't significantly closer to the moon than we are. Anyway, for the size of telescope and the distance to the moon, the smallest things Hubble could pick up are about the size of a football field. So this telescope couldn't see the lunar modules even if it WAS pointed at the moon. Third, there are much more important things to do with the telescope than to convince a bunch of conspiracy nuts that there was a moon landing. NASA *knows* there was a moons landing. Also, any pictures taken of the landing sites would be declared fake by the nuts anyway. So what's the point?

  • shetan
    Lv 4
    4 years ago

    Moon Filter

  • 1 decade ago

    First, NEVER look through a sun filter that connects to the eyepieces! They heat up and crack allowing the sun's light through which can damage the eyes. ONLY use solar filters that go on the front of the telescope!!!!!

    As for the moon filter:

    You don't absolutely need it for safety reasons to look at the moon. The light from the moon will not damage your eyes in the way that the light from the sun will.

    However, the glare from the moon will be enough that you won't be able to resolve fine details that you could if you have a lunar filter. Also, the moon is bright enough that you will have to re-adjust your night vision if you want to go back to see other sights like galaxies or double stars. A lunar filter will reduce the amount of time needed for this adjustment.

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  • 1 decade ago

    The moon filter is merely an observation aid - will make your observing better.

    A Sun filter is a safety must-have if you are planning to do any sun observations. Looking at the sun without a telescope without proper protection is very bad already. doing it through a unfiltred telescope you risk blindness (and damage to your telescope as well as lenses or mirrors inside will get quite hot).

    The reason why one may wish to use a moon filter is to reduce glare and be able to spot more detail. You can observe the moon without a filter. here are som e tips:

    1) Never observe the full moon. there is no risk to your eyes but the sun is shinning on the moon surface directly from above. There are no shadows and contrast is very poor, even with a moon filter.

    2) Observe the moon when it is less than 1/4 full (or more than 1/4 towards the Full Moon). Shadows will bring up surface features (craters, hills, roughness) and you will be able to see more detail.

    3) The moon is so bright you can eaasily use maximum magnification.

    4) Still find it too bright and poor contrast? Try using a pice of cardboard with a small circular hole (1 to 2 inch) to cover the objective of your telescope. This lets less light come in and should improve contrast for Moon observing. My guess is you won't need it if you stick to the less than 1/4 full "rule".

  • 1 decade ago

    Two things. First, to say "never look at a full moon" is wrong. It won't hurt your eyes. You can look at the moon any time you want. A full moon will not show much detail, because you are not seeing any shadows, but there is no rule against it. I cannot believe the number of parrots who repeat this silly "rule". And as far as I am concerned, it is quite stunning. Second, never ever look at the sun through a telescope, no matter what anyone says, even with some kind of filter. Those filters may or may not effectively block damaging rays, and unless you feel like taking a chance with your vision, use a projection screen instead. As far as a moon filter, it is a neutral-density filter that makes it easier to look at the full moon for extended times, because it is so bright that it is uncomfortable to look at for a long time, kind of like staring at a light bulb. It also increases the contrast of the light and dark regions of the moon, which helps you see more detail.

  • 5 years ago

    This Site Might Help You.


    Do I need a "moon filter" for my telescope?

    Will it hurt my eyes at night if I look at the moon through my telescope? The telescope says it doesn't come with a moon nor sun filter.

    Source(s): quot moon filter quot telescope:
  • GeoffG
    Lv 7
    1 decade ago

    No. The surface of the Moon is the colour of asphalt. It only appears bright to our eyes when we view it in a dark sky from the dark surface of the Earth. Seen in the daytime sky, it's barely visible. So there's no more danger in looking at the Moon than in looking at a distant mountain in daylight.

    I'm a serious lunar observer. I never use a Moon filter myself, even on scopes as large as 11 inches aperture. I deal with the brightness in several ways. I often observe the Moon in twilight. I use a white light in my observatory to consult my Moon maps. I use high magnifications (at least 250x) and often a binoviewer, which cuts the light reaching each eye in half. I find that Moon filters are generally made from cheap glass and seriously degrade the sharpness of the image, as well as introducing false colour.

    Save your money and buy a full aperture solar filter instead. These are essential for viewing our Sun, one of the most fascinating objects in the sky. The best filters use Baader film. You can make your own with film purchased from Astro-Physics, or buy one in a nice aluminum cell made by Jim Kendrick:

  • 5 years ago

    do i need a moon filter to take photos

  • Anonymous
    1 decade ago

    Forget the sun.

    The moon will not damage your eyes through a scope, but it can be uncomfortably bright to the point that you have to stop looking. You don't need one, but it can be a help when observing for long periods at a full or near-full moon.

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