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NightHawk · Joined: 05 Dec 2006 Posts: 37 Location: Dalgety Bay

I'm thinking of purchasing a telescope in the near future.

I was told by somebody a while ago, that you need a filter for looking at the moon since it is so bright. It has been on my mind for a while now.

Is this true?

Any explanations or advice appreciated. Thanks Very Happy

pbholmes · Joined: 15 Nov 2006 Posts: 141 Location: Dalgety Bay

I know you can get them, e.g. from
http://www.celestron.uk.com/catal...;CategoryID=3874&ItemID=30993
but I've never used one myself.

With my compact and bijou 114mm Newtonian, I've looked at the moon a few times without finding it painfully bright.

I've never looked at the moon through a bigger scope, so maybe you need one for those.

Solar B · Joined: 07 Dec 2006 Posts: 105 Location: Dalgety Bay

unless you are using a very large aperature telescope ie 250mm on a near full moon you should not need a polarising filter to cut the glare.
brian Very Happy

NightHawk · Joined: 05 Dec 2006 Posts: 37 Location: Dalgety Bay

Thank you for your replies.

I don't know much about sizes.

The person that told me about the filter worked with the 10" and 16" at my university. Thanks for clearing things up! (250 millimeters = 9.84251969 inch)

You are saying that 250mm is large. They have a 37"! I never saw that one though. Must be enormous!

Solar B · Joined: 07 Dec 2006 Posts: 105 Location: Dalgety Bay

Even if you were thinking of purchasing a large app telescope a polarizing filter for your eye piece would only cost about £11 and you could have
mine at any time. brian Smile

bhenderson50 · Joined: 11 Dec 2006 Posts: 48 Location: dalgety bay

I have been observing the moon through my 12" scope, and although it appears bright at first, the eye pupil soon contracts to compensate. I don't think a moon filter is necessary - just don't try observing any faint objects any time soon afterwards! You will not be able to see too much for a few minutes after.
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bobh