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Date: 19 Sep 2007 15:51:36
From: thew
Subject: The seeing was good, the finder scope wasn't
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I got off a good session yesterday with my 6" reflector, despite being
new to this. But I really, really loathe this 5x24 finder scope. It's
tiny and even the brightest stars look dim through it. Will replace it
with a better one.
In spite of that, I bagged a couple different objects. Because Jupiter
is setting early now, I went out right at sunset. I only have a Kellner
25mm eyepiece and a Plossl 15mm (48x and 80x, repectively) so far. With
the 25mm, Jupiter looked like a white dot with the moons on either side
of it. With the 15mm, it looked like a bigger white dot. I could then
just about see a cloud band or two. I'm going to get a Barlow lens soon.
It's getting late for Jupiter, but Mars is coming up.
And of course the Moon. With the 15mm eyepiece, it just about fills up
the entire field of view.
Then looked at the Lyra Double-Double, but I apparently don't have
enough magnification to resolve the two pairs of stars. I also couldn't
see Zeta Aquarii or Gamma Delphini, both tight doubles.
But I did get the Ring Nebula. At either magnification, it looks like a
nice little gray donut. Tried to find the Dumbbell Nebula, but couldn't
see it. I also couldn't see the North America Nebula to save my life.
Got Albeiro in Cygnus (easy), and Gamma Andromedae (another nice orange
and blue double).
M13 just looked like a gray cotton ball at either magnification,
although with the 15mm I could make out it's stars with averted vision.
Also got M15 in Pegasus.
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Date: 19 Sep 2007 19:13:03
From:
Subject: Re: The seeing was good, the finder scope wasn't
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On Sep 19, 9:51 am, thew <t...@enter.net > wrote:
> I got off a good session yesterday with my 6" reflector, despite being
> new to this. But I really, really loathe this 5x24 finder scope. It's
> tiny and even the brightest stars look dim through it. Will replace it
> with a better one.
Good idea! It's amazing how much of a difference a *good* finder (or
two) can make.
> In spite of that, I bagged a couple different objects. Because Jupiter
> is setting early now, I went out right at sunset. I only have a Kellner
> 25mm eyepiece and a Plossl 15mm (48x and 80x, repectively) so far. With
> the 25mm, Jupiter looked like a white dot with the moons on either side
> of it. With the 15mm, it looked like a bigger white dot. I could then
> just about see a cloud band or two. I'm going to get a Barlow lens soon.
> It's getting late for Jupiter, but Mars is coming up.
Yep, a bit more magnification seems to be called for. Precise
collimation can also make a *noticeable* difference when it comes to
observing the planets.
> But I did get the Ring Nebula. At either magnification, it looks like a
> nice little gray donut. Tried to find the Dumbbell Nebula, but couldn't
> see it. I also couldn't see the North America Nebula to save my life.
Perhaps the scope wasn't quite pointed at M27? The Dumbbell should be
plenty bright enough for you to see.
The North America Nebula is *huge*! One of my best views was an
accidental encounter. I was sweeping the sky for comets several years
ago using a 25cm Newtonian one night when suddenly the entire field of
view (and then some) became flooded with "bright" nebulosity (complete
with a considerable amount of visible structure). I took some time
out from my sweeping to scan the region (including the Pelican Nebula)
with my low-power, wide-field eyepiece before resuming the hunt. This
was from a magnitude 6.5 or better sky.
I suspect that many people (under less ideal skies) mistake the rich
Milky Way in the area for the nebulosity. With a telescope it ought
to be possible to clearly tell whether or not one is seeing the
nebulosity.
Under sufficiently light polluted skies the North America Nebula
*might* be rendered invisible (at least without a 'nebula' filter of
one kind or another). The nebula's large size (especially when
combined with a bit of light pollution) can also turn it invisible in
some telescopes at some magnifications.
> Got Albeiro in Cygnus (easy), and Gamma Andromedae (another nice orange
> and blue double).
Those are very nice doubles!
Bill Greer
To sketch is to see.
http://cejour.blogspot.com
http://www.rangeweb.net/~sketcher
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Date: 20 Sep 2007 04:10:29
From: thew
Subject: Re: The seeing was good, the finder scope wasn't
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> Yep, a bit more magnification seems to be called for. Precise
> collimation can also make a *noticeable* difference when it comes to
> observing the planets.
True. You need 100x or greater for the planets. A 2x Barlow would take my
15mm eyepiece up to 160x. Especially since this upcoming Mars opposition
won't be as good as the past three ones. Too bad you can't see Saturn now
unless you're willing to get up at 5:00 in the morning. I suppose I should
have tried for Uranus (easy enough to find), but 80x is not enough
magnification to make out it's disk.
>> But I did get the Ring Nebula. At either magnification, it looks like a
>> nice little gray donut. Tried to find the Dumbbell Nebula, but couldn't
>> see it. I also couldn't see the North America Nebula to save my life.
>
> Perhaps the scope wasn't quite pointed at M27? The Dumbbell should be
> plenty bright enough for you to see.
This evening I tried M27 again and failed. I centered on Gamma Sagittae and
moved straight up, but nothing. I also tried M71, between Gamma and Delta
Sagittae, but missed that too.
> The North America Nebula is *huge*! One of my best views was an
> accidental encounter. I was sweeping the sky for comets several years
> ago using a 25cm Newtonian one night when suddenly the entire field of
> view (and then some) became flooded with "bright" nebulosity (complete
> with a considerable amount of visible structure). I took some time
> out from my sweeping to scan the region (including the Pelican Nebula)
> with my low-power, wide-field eyepiece before resuming the hunt. This
> was from a magnitude 6.5 or better sky.
You must have had a 2" eyepiece. My 6" reflector can't use those.
> I suspect that many people (under less ideal skies) mistake the rich
> Milky Way in the area for the nebulosity. With a telescope it ought
> to be possible to clearly tell whether or not one is seeing the
> nebulosity.
The NA Nebula should be simplicity itself to find, being right next to
Deneb, but all I saw was darkness. The sky this evening was not
particularly good because of the brightness of the first quarter Moon.
> Under sufficiently light polluted skies the North America Nebula
> *might* be rendered invisible (at least without a 'nebula' filter of
> one kind or another). The nebula's large size (especially when
> combined with a bit of light pollution) can also turn it invisible in
> some telescopes at some magnifications.
>> Got Albeiro in Cygnus (easy), and Gamma Andromedae (another nice orange
>> and blue double).
I tried Gamma Delphini again this evening and got it. Zeta Aquari is too
tight (heard that you need 100x magnification to split it). I also tried
Polaris. At 80x, I could see it's 9th magnitude companion. And also looked
at Mizar in the Big Dipper (easy double). Looked for M101, but couldn't see
it (but then the BD is awfully low in the sky this time of year).
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Date: 19 Sep 2007 12:48:49
From: William Hamblen
Subject: Re: The seeing was good, the finder scope wasn't
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On 19 Sep 2007 15:51:36 GMT, thew <thew@enter.net > wrote:
>I also couldn't see the North America Nebula to save my life.
The North American Nebula is a real noseeum. I've made a slide of it
from my back yard, but I can't see it in the eyepiece.
Bud
--
The night is just the shadow of the Earth.
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Date: 21 Sep 2007 01:27:46
From: David Knisely
Subject: Re: The seeing was good, the finder scope wasn't
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Try using either a good Oxygen III (OIII) filter or the DGM Optics NPB,
and do it under a dark sky. In a rich-field scope with over two degrees
of true field, it is pretty easy with a filter, but rather diffuse and
hard to see without one. Clear skies to you.
--
David W. Knisely KA0CZC@navix.net
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/
**********************************************
* Attend the 14th Annual NEBRASKA STAR PARTY *
* July 15th-20th, 2007, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
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Date: 19 Sep 2007 18:55:58
From: Marty
Subject: Re: The seeing was good, the finder scope wasn't
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>The North American Nebula is a real
> noseeum. I've made a slide of it from
> my back yard, but I can't see it in the
> eyepiece.
Actually, it's one of those things that's kind of hard to see on account
of it's large size. Under darkish skies, it shows up as a bright patch
of the Milky Way to the naked eye. Once you've located it that way, it
starts to show it's shape, (ie. the gulf of Mexico,) with binoculars.
Marty
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Date: 19 Sep 2007 18:17:56
From: thew
Subject: Re: The seeing was good, the finder scope wasn't
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William Hamblen <wrhamblen@comcast.net > wrote in news:
> The North American Nebula is a real noseeum. I've made a slide of it
> from my back yard, but I can't see it in the eyepiece.
Well put. For being 6th magnitude, the NA Nebula is sure pushing it. I also
have two pairs of binoculars (7x35 and 12x50) and I cannot see it in either
of them.
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