[Chaos-l] Narrowband filters?

[Michael Hrivnak]

I'm not aware of any galaxies that benefit from the use of these
filters, and I think most will just be dimmer.

H-beta is good for only about three objects.  Most people buy it just
so they can see the horsehead nebula (which requires a H-beta, and
even then it's a challenge), but it's also useful on the California
nebula and maybe a couple of others.  I think it's safe to say that
this would not be the best first-filter purchase.

O-III and UHC filters are generally the best for emission nebulae.  I
tend get a better view with my O-III filters as opposed to my UHC, but
I haven't done a lot of experimenting with different brands.  Thousand
Oaks is another brand to consider.  I have at least one filter from
them.

As always, I'm a big fan of getting stuff from astromart.com.  Right
now, there are 1.25" Lumicon filters in the O-III and UHC variety for
$60 each.

Of course it's always most useful to get out on the field and borrow
filters from other people to see how they perform in your scope.

Michael

On Sat, Apr 28, 2012 at 7:26 PM, Alexey Toptygin <alexeyt at freeshell.org> wrote:
>
> I've been considering getting a narrowband filter (O-III and H-beta). I've
> read that they improve contrast when viewing emission nebulae. I have some
> questions that I hope folks here can help with:
>
> Can they also be used to improve views of galaxies?
>
> I assume they're not useful for clusters and dark and reflection nebulae,
> since most of the interesting light there will be H-alpha?
>
> I've been looking at the Orion UltraBlock, the Lumicon UHC and the TeleVue
> Bandmate Nebustar. They are all around the same price (about $100 for
> 1.25").
>
> I can't tell what the actual pass band is for the TeleVue (I can only find
> this info for the other two) does anyone know where I can find it?
>
> Does anyone have experience with these particular filters?
>
>                        Alexey
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