When using an 8" MCT, how much blockage do I need for the moon filter? It seems there's 25%, 13% and 9%. Which one do I need?
Its blinding otherwise..... sunglasses actually do a decent job for now!
How much light blockage do I need for a Moon filter?
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Wow. You getting a 8" MCT?
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email: gary[at]astro.sg
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"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
email: gary[at]astro.sg
twitter: @astrosg
"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
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Eh no lar, its a modified MCT, more of a Klevtsov. Definitely not one of the extremely expensive, highly premium Maks that cost thousands of USD 
Its light grasp has been rated as slightly less than a C8 due to the corrector lens.
Anyway, so what kind of light transmission should I choose? A Variable Pol. is about 3-4x as expensive as a fixed one and no one seems to make stand alone 2" Polarizers or else I'd just gang up 2 of them on my own.
Its light grasp has been rated as slightly less than a C8 due to the corrector lens.
Anyway, so what kind of light transmission should I choose? A Variable Pol. is about 3-4x as expensive as a fixed one and no one seems to make stand alone 2" Polarizers or else I'd just gang up 2 of them on my own.
DON'T PANIC
I cant understand the need for moon filter for visual work. It's bright but so what? If the skies are good and one wants to preserve dark eye adaption, observe near/on a new moon day or just ignore the moon and observe other stuffs. If one wants to observe the Moon, the best time is not full moon anyway and other phases are not really that blinding (to me at least).
Anyway, send us some pics of your modified MCT like yesterday!
Anyway, send us some pics of your modified MCT like yesterday!
http://www.astro.sg
email: gary[at]astro.sg
twitter: @astrosg
"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
email: gary[at]astro.sg
twitter: @astrosg
"The importance of a telescope is not how big it is, how well made it is.
It is how many people, less fortunate than you, got to look through it."
-- John Dobson.
Neutral density filter
The neutral density filter that comes with my eyepieces has 13% transmission (Meade ND96). The instructions state it is for telescopes 4 inch and larger. Certainly it helps reduce the glare and make it easier to see details on the Moon surface.
Hope that is helpful
Hope that is helpful
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- Joined: Mon Jul 12, 2010 6:08 pm
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Thanks DC! After some searching I think I'm going to need something less than 13%.... the moon was still blinding even after wearing my driving sunglasses! So it looks like variable filters for me.
Does anyone know if GSO still produces the 2" polarizers? I figure its cheaper to buy 2x 2" polarizers, fit one into the diagonal and the other into the eyepiece and just rotate the eyepiece to adjust the light transmission than it is to buy a dedicated variable polarizer.
But the Lumicon for $47 shipped is tempting....
Does anyone know if GSO still produces the 2" polarizers? I figure its cheaper to buy 2x 2" polarizers, fit one into the diagonal and the other into the eyepiece and just rotate the eyepiece to adjust the light transmission than it is to buy a dedicated variable polarizer.
But the Lumicon for $47 shipped is tempting....
DON'T PANIC