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ksodbartman
2005-Mar-26, 09:00 PM
I bought a Meade ETX-125 a while ago and just ordered a laptop to go along with the free LPI that came with it. I already have the five-filter set Meade sells, but am going to buy another filter to burn up the gift certificates from Discovery Store that I got. What are your opinions on the best overall filter of these three, if you can only have one:

Meade #908N Narrowband Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=12287&partnumber=711564)
Meade #908B Broadband Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=12394&partnumber=305037)
Meade #908X Oxygen-III Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=10944&partnumber=327767)

I live a decent distance from major cities, so light pollution isn't as big a problem as some might have...

ngc3314
2005-Mar-26, 09:38 PM
I bought a Meade ETX-125 a while ago and just ordered a laptop to go along with the free LPI that came with it. I already have the five-filter set Meade sells, but am going to buy another filter to burn up the gift certificates from Discovery Store that I got. What are your opinions on the best overall filter of these three, if you can only have one:

Meade #908N Narrowband Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=12287&partnumber=711564)
Meade #908B Broadband Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=12394&partnumber=305037)
Meade #908X Oxygen-III Nebular Filter (http://shopping.discovery.com/stores/servlet/ProductDisplay?catalogId=10000&storeId=10000&langI d=-1&productId=10944&partnumber=327767)

I live a decent distance from major cities, so light pollution isn't as big a problem as some might have...

(Warning - the following is based on experience with fairly similar filters from other manufacturers) I'd suggest the broadband nebular filter. Even with fairly dark skies, this will noticeably improve the contrast of faint details (such as the outer loops of the Orion Nebula) without knocking out the stars too much (as long as you like green). It also works about equally well for nebulae with stronger [O III] (planetaries) and Hydrogen lines (many of the nebulae ionized by young stars). And from a more light-polluted area, in working with classes and public groups, I've found that a similar filter gets good reviews for improving the views of Orion and bright planetaries, and makes all the difference between seeing and not seeing some things of lower surface brightness (M76 comes to mind).

frogesque
2005-Mar-28, 11:46 AM
Well, if you are really feeling flush you could get an H-alpha filter. (http://www.daystarfilters.com/hydrogen.htm)

aurora
2005-Mar-29, 09:30 PM
(Warning - the following is based on experience with fairly similar filters from other manufacturers) I'd suggest the broadband nebular filter.

Of the three listed, I would vote for the narrowband filter. Or maybe the OIII.

IMO, broadband filters are of limited usefulness. Either the narrowband or the OIII will help significantly with various nebula. The broadband is usually called a light pollution filter, and I don't think they really filter much...

Some objects are better in the narrow band, others in an OIII. Off the top of my head, IIRC, a narrowband is better on some emission nebula like the Orion Nebula or the Lagoon, while an OIII is better with supernova remnants like the Veil.

Or I might have that backwards.

But if you can only afford one, and you will be looking at a variety of objects, it probably doesn't make that much difference which you choose.

Charlie in Dayton
2005-Mar-30, 02:16 AM
...for just a split micro-instant, gazing at the title of this thread, I thought it was an extension of Candy's 'do you smoke' thread...

And by the way, more opinions on this thread would be welcomed...I'm sorta kinda thinking of getting some sort of nebularizer myself...

aurora
2005-Mar-31, 06:16 PM
And by the way, more opinions on this thread would be welcomed...I'm sorta kinda thinking of getting some sort of nebularizer myself...

This article does a good job of summarizing the different types.

http://www.astronexus.com/gatfaq/filters.php

It reinforces the point I was trying to make:


If you have only enough money for one filter, I suggest getting a good narrowband version, like the Orion UltraBlock or Thousand Oaks LP-2 (Narrowband). One of these will optimize viewing of nebulas under all sky conditions.

If you have enough to buy two, a narrowband filter plus a line filter would be a good combination. The OIII is the most versatile of the line filters and is very highly recommended; the H-Beta tends to be a specialty filter (see below for more details). For objects where the OIII filter isn't so great, you'll often get good results with the regular narrowband filter.