Quote:
Originally Posted by aad_Dira
so, do you mean that the variable polraizing filters is the best for a beginner? and what is the good amount of light reducing for me? is 1 to 40% good? most of the filters i have found have this amount light reducing.
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With a polarising filter set, you vary the amount of light getting through according to what you need by rotating the filters against each other. If it is near full moon, then probably as much as you can. If Jupiter, maybe just a single filter is needed. Light reduction is roughly 50% with a single filter, and nearly 100% with both in the correct orientation.
Quote:
Originally Posted by aad_Dira
you are really "refreshing" me. but there is another point, that is you are observing in Sydney from a southern sky, but i am here observing from a northern one. i don`t know how much it is different, but here i think that the brightest nebula is Orion nebula, so, other than it and Andromeda and its staellites, i don`t think that there is a nebulae or galaxies less than 8+ mag in our sky, at least very few.
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You want to know what is observable, you can start with the entire Messier catalogue. You should be able to observe just about them all, even from a city site. M1 probably the only one not visible in small scopes as it has dimmed since it was first seen by Messier.
Quote:
Originally Posted by aad_Dira
but, the nebulae is a faint object, and the filter will reduces more of its valuable light, why it is still good for the city observations? and even your saying that "They can actually make a real difference in see them or not".
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Nebulas glow at very specific wavelengths of light. Have you noticed how in pictures they are only red, blue or both. These nebula filters absorb all wavelength of light and only transmit those at which nebulae glow at. In a light polluted sky, these filters aid in reducing the background sky glow, so showing nebulae as their light is still transmitted.
Quote:
Originally Posted by aad_Dira
i already have a binocular, but it is not useful with nebulae, just for stars.
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You think you can't see nebulae with them, use them to view the Scorpio/Sagittarius region of the sky.
If there is no active astronomical club or society, it might be an opportunity to start a group, even if only as a social get-together. I'm not a member of an astro club, other than here on IIS, but I organise a monthly get-together during the new Moon weekend to a location two hours drive from my home to a dark site. People have also come without a telescope, but with bucket loads of enthusiasm.
Mate, the joke was noted too,
!