I currently own a Celestron 9 1/4 sct and am considering a Obsession 18". I live in Napa , Ca. and am concerned if light pollution will negate the larger aperature or if I will still gain "seeing" despite the the amount of light pollution here. With my current 9 1/4" I can see some of the brighter galaxies ,just make out the faint images of the Little dumbell nebula and the crab. How much improvement will I get with an 18" at this location based on the info I just gave.

The answer is it depends on the type of object you are looking at. However, for most deep sky objects aperature wins regardless of whether you are in the suburbs or in the outback.

Hi everyone-Im Thomas and I live in the UK. Some of you may have seen me from other forums.

Another thing that effects a scopes performance according to the text books is the focal ratio. In light polluted areas a higher focal ratio tends to cut through the pollution better. However I used to own an F4 16" scope which I used from my light polluted home and it seemed to be fine.

Rules of Telescopy:

1) More aperture is better.

End of rules. [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

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It's just one of those damn things of which there are many few. -- Dan Blocker

Actually, I was at a star party one night when it was extremely clear, but extremely windy. My little 5 inch SCT was one of the few instruments stable enough to give decent views. While all the large telescopes (up to 36") were worthless, I had a line waiting to look through my 5". The skies were clear and everyone was impressed with what you can see through a small telescope (we saw 7 galaxies in a cluster in Leo in one field of view!)

Rob

I have a nice little 3-1/2 inch Questar which is great for planetary astronomy near my home (despite the light pollution).

If I want more aperture, etc., I peek through my friends' scopes (most of which are huge) at my astronomy club's dark site.

Belonging to a wonderful astronomical club makes life very pleasant. I get the best of both worlds!

ljbrs [img]/phpBB/images/smiles/icon_biggrin.gif[/img] [img]/phpBB/images/smiles/icon_smile.gif[/img] [img]/phpBB/images/smiles/icon_wink.gif[/img]

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"There is in the universe neither center nor circumference." Giordano Bruno Born 1548. Torched 1600.

To say the Questar 3 1/2 is "nice" is a gross understatement. Beautifully crafted instrument that vastly out-performs its aperture! Wish I could afford one. [img]/phpBB/images/smiles/icon_cool.gif[/img]

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TANSTAAFL!

<font size=-1>[ This Message was edited by: Kaptain K on 2002-01-28 22:37 ]</font>