(kowen) wrote in message om...

I live out in the country, no city light pollution, but do have a
streetlight- 350 ft to the east, a closer flood on top of a post-about
65 ft. east, and a neighbor's backyard flood, about 500 ft N/NE.

The streetlight shouldn't do any harm at all as long as you can find
some way to block its direct light, but it would be awfully nice if
you could do something about that light 65 feet away. If not, can't
you find somewhere nearby that's far from any lights? I have to drive
2 hours to get to dark skies; you should be willing to go 5 minutes.

If my average mag skies are 4.3 (Zeta Lyrae) or perhaps a little
better, might I benefit from a UHC filter? ...
I have Orion's XT4.5, 3 years the end of this October-a keeper ...
have the XT8 on the way ...

I imagine that once the drier air of winter sets in, your limiting
magnitude will be *much* better than 4.3. Anyway, yes a UHC or O-III
filter makes a major difference for viewing the big, faint nebulae,
notably the North America and the Veil. In general, I don't find
filters very helpful for small, bright planetary nebulae like M57.
It's often interesting to see how a filter changes the view of
such a nebula, but I would say that the view is different rather
than better. Oh yes, and filters are *definitely* helpful for
finding those pesky little planetary nebulae in the first place.
Just pass the filter between the eyepiece and your eye and the
nebula usually pops right out, as the stars dim but the nebula
remains almost unaffected.

However, the jump from 4.5 to 8 inches of aperture is so vast
that almost everything in the sky will look dramatically better.
That's a much bigger change than buying a filter.

- Tony Flanders