Backyard planetaries, TV76, 9/13/2004

Date: Monday evening, 13-Sept-2004
Location: Backyard, Palm Springs, California
Equipment: Tele Vue 76 (3" f/6.3) refractor

I've been sort of hooked on a few little planetary nebulae lately.
Tonight i found NGC 6572 in Ophiuchus for the first time. Through the
TV76 at 30x looks like a star. But with the 7mm for 68x it looks quite
a bit like a little planet. I've seen this planetary referred to as
the "Blue Racquetball" but i don't see the blue color tonight. Using
the UHC filter the nebula really pops out of the background.

Since i was in the area i checked open cluster NGC 6633. Fairly spares
and coarse. Seems somewhat triangular in shape. Also open cluster IC
4756 in Serpens is large with mostly dim members. Reminds me of the
Beehive in Cancer.

Back to planetaries for the 3 i've been tracking lately... NGC 6543 in
Draco, NGC 6826 in Cygnus, and NGC 7662 in Andromeda. I think 6543 is
the brightest of tonight's four and 6826 the faintest. 6572 is
definitely the smallest. All are somewhat similar yet different in
their own ways.


-Florian
Stargazing.com

Florian,

I found your post interesting.
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.

I think the area West-North is my best hope for seeing, as there is an
empty field behind my house (west) and a pasture behind my neighbor's
house (north) that goes far to the west. I have seen the 12-Gamma-1
Delphini star, naked eye, 5.15 mag in Delphinius, when seeing allowed.

If my average mag skies are 4.3 (Zeta Lyrae) or perhaps a little
better, might I benefit from a UHC filter? I'm thinking about getting
one of these-an Astronomiks, but have read ultimately they work best
at dark sky sites-not hard to believe. I do get those few rare
evenings where it seems there is sugar sprinkled on black velvet-nice,
steady, clear nights. Can you tell me what mag skies are in your
area?

Another example, I can see the three main stars of the Triangulum
(4.03 Gamma Trianguli)on a regular night, even thought that area of
the sky has the streetlight, and one much further NE up the highway.
Of course, through binoculars or the scope I can see the "invisible"
higher mag stars.

I have Orion's XT4.5, 3 years the end of this October-a keeper, good
grab & go-no Televue refractor here-and with the Skyquest Classics
going on sale, have the XT8 on the way (talk about new scope
curse...). I found M57 a few weeks ago-I've been lagging on finding
objects-so I'm spurred on to find more. Any insight into this would
be appreciated.

Clear skies,
Kerry
s.e. Louisiana

If my average mag skies are 4.3 (Zeta Lyrae) or perhaps a little
better, might I benefit from a UHC filter? I'm thinking about getting
one of these-an Astronomiks, but have read ultimately they work best
at dark sky sites-not hard to believe.


Hi Kerry,

My UHC filter is also an Astronomiks. I don't really use it too much but =

once i a while on planetaries and things like the Veil it's quite =
helpful.
My backyard skies are around a Bortle class 6...

http://www.novac.com/light/def.htm

I only tried the UHC the other night just to see what kind of difference
it would make. I generally perfer the few without the filter.=20

-Florian

For the smaller planetaries, I believe an OIII filter is the better choice,
but the UHC can do wonders at knocking back the light pollution and drawing
out emission nebula such as the Lagoon, the Trifid, the Swan, and even The
Great Nebula in Orion in Winter. I've never had a lot of luck with detail in
The Eagle Nebula, other than seeing a ghost of whispy illumination, but
still the difference with and without is pretty striking. Definitely worth
the cost of admission in my opinion.

My zenith is around magnitude 5.5 on any decent cloudless night, and can
reach 5.7 depending on the transparency and seeing. Down on the south
horizon where the best of the summer nebula can be found, the sky quickly
dives down to around magnitude 4. This is where the filter really helps me
out with the aforementioned nebula.

I made a run at the summer planetaries a few nights ago and found the UHC to
be only a marginal help on the smaller, brighter ones. The UHC really seems
to pay off in pulling out the larger diffuse nebula. Whether planetary or
emission. That includes the Owl Nebula as well. Any that are dim and
somewhat large compared to the several smaller planetaries.

YMMV
-Stephen


"kowen" wrote in message
m...
Florian,

I found your post interesting.
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.

I think the area West-North is my best hope for seeing, as there is an
empty field behind my house (west) and a pasture behind my neighbor's
house (north) that goes far to the west. I have seen the 12-Gamma-1
Delphini star, naked eye, 5.15 mag in Delphinius, when seeing allowed.

If my average mag skies are 4.3 (Zeta Lyrae) or perhaps a little
better, might I benefit from a UHC filter? I'm thinking about getting
one of these-an Astronomiks, but have read ultimately they work best
at dark sky sites-not hard to believe. I do get those few rare
evenings where it seems there is sugar sprinkled on black velvet-nice,
steady, clear nights. Can you tell me what mag skies are in your
area?

Another example, I can see the three main stars of the Triangulum
(4.03 Gamma Trianguli)on a regular night, even thought that area of
the sky has the streetlight, and one much further NE up the highway.
Of course, through binoculars or the scope I can see the "invisible"
higher mag stars.

I have Orion's XT4.5, 3 years the end of this October-a keeper, good
grab & go-no Televue refractor here-and with the Skyquest Classics
going on sale, have the XT8 on the way (talk about new scope
curse...). I found M57 a few weeks ago-I've been lagging on finding
objects-so I'm spurred on to find more. Any insight into this would
be appreciated.

Clear skies,
Kerry
s.e. Louisiana

(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...

If my average mag skies are 4.3 (Zeta Lyrae) or perhaps a little
better, might I benefit from a UHC filter?

Your skies and situation sound vaguely similar to mine. I've got nice
rural skies with a few local streetlamps for that added irritation
factor.

I think you'll find a UHC will work fine for you - there's nothing
about your skies to prevent it functioning as designed. However, you
may find catching brief sight of the lights around your observing site
will affect your dark adaption quite badly and THAT will impact the
efficacy of any UHC or "nebula" filter.

I learned this from saa after complaining that I was unimpressed with
the performance of the Meade 2" Nebular (sic) filter. Someone
suggested I wasn't dark adapted enough to get the full benefit and
subsequent experimentation proved them right. Learning all the time...

Cheers
Beats

(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

An inexpensive observatory might be the answer for you. There are many
ideas out there. I have to drive to get to dark skies (about an hour), but
since you live in a rural area, it seems a homemade observatory or merely a
permanent stray light shield around your observing place might do the trick
for you. I know I'd do a lot more DSO observing if I didn't have to drive.

--

Clear Skies,

Chuck

"Tony Flanders" wrote in message
...
(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

I just wanted to add the one object i find that really benefits from a =
UHC
filter is M76, the Little Dumbbell in Perseus. M76 is almost invisible
through my home skies without the filter but with the UHC the nebula
becomes quite easy. Almost bright! ;-)

-Florian

Florian-
I'd prefer not using a filter if I didn't have to also-that coming
from an amateur photographer's point of view-keep the view clean.
However, after reading your's and these replies it looks like I may be
out another $100 in the near future. This hobby is a wallet killer.
Then Stephen reminds me about the OIII filter...I believe what he &
Tony say about that...I'm open to that one as a 3rd filter, but would
wait a while...

I had been noticing all the planetaries & galaxies-looks like a
zillion-when you zoom in using the Sky software. Seems like there is
allot to see right now. Tonight would be good for viewing, but have
to re-lign up the XT4.5-my @#$% primary has one collimating screw that
has no adjustment turn left to it, so have to re-square/re-shim the
focuser. (I should have left it like I fixed it before...).

Tony,
I will give the XT8 a run through before buying any filter-I agree the
aperture and resolution increase would have to improve detail in the
views. That M57 was interesting-definitely not a hubble twin from my
small scope but interesting enough. Mississippi is about 2 hours
away-how's that? The Deep South Regional Stargaze will be out there
mid October, will try to attend. I observe by myself 99% of the time,
so going elsewhere in this small community to maybe setup the XT8
would get you a bit noticed. I can put it in the field behind the
house and oak tree=streetlight blocker . Raccoons are cute but they
can have attitude-and rabies. I'm not crazy about running into one of
those...

Chuck,
I'd like one on the roof-just go upstairs and see what's what. That
ain't gonna happen too soon. I also thought about one in the back
field...When you get into this hobby you can't help but look those up
on the internet...I've seen the light blocking screens, those look
okay. Backyard behind the house helps but the tree tops are there-we
can't have it all.

Beats,
I hear you about the stray light hitting the eye/ep/etc. That is
aggravating. I have an eyepatch that I use now & then. In the winter
I use another jacket or so to cover my head, like a photographer's
hood. I have some black felt material, I might use that, I know Orion
has one-the Observer's Hood. Something for everyone. I've had to
watch that the ep doesn't fog from exhaled warm air building up. If
you aren't a salesman you're a good one anyhow.

Thanks for all the helpful advice, I will be penniless.

Regards,
Kerry

"Florian" wrote in message ...

The one object i find that really benefits from a UHC
filter is M76, the Little Dumbbell in Perseus. M76 is almost invisible
through my home skies without the filter but with the UHC the nebula
becomes quite easy. Almost bright! ;-)

I think that depends on the size of your scope. In my 70mm scope, M76
is a pretty faint object even under dark skies, and bright skies make
it marginal indeed. So M76 is definitely easier to find from the city
in my 70mm scope when I'm using a filter. On the other hand, filter or
no, the 70mm scope isn't *quite* big enough to show interesting detail
in this object -- it looks elongated, but that's that.

The story is completely different in my 7-inch Dob -- which *is* big
enough to give a very interesting view of M76, city or country, filter
or no filter. Due to its extremely high surface brightness, M76 jumps
right out in that scope even when I'm viewing from the city, even
at very low power. Under dark skies, the filter gives a *different*
view of M76, but I wouldn't necessarily say a better view. Parts of
M76 that show well without a filter become fairly obscure with one,
and vice versa.

So I would say that this is a case, as with other small bright
planetaries, where a filter makes the object easier to find but
not necessarily better to view. And in a scope big enough to do
the object justice, it's pretty easy to find even without the
filter.

- Tony Flanders