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Main
Date: 21 Jun 2007 15:18:54
From: Anthony Ayiomamitis
Subject: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
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Dear Group,
With Cygnus slowly getting into good position for imaging, there is a
wide variety of goodies it provides for the interested observer and imager.
Given the plethora of Barnard dark nebulae it offers, I thought I would
try my hand with one of the largest such objects just north of the
bright star Sadr.
More specifically, I pursued B343 which lies within a couple of degrees
just north of Sadr. For an image based on four hours total exposure, I
kindly direct you to
http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first
attempt at a dark nebula and I would welcome all feedback. I have
checked around and cannot find any reference images for comparison B343
... if someone has pursued this particular object, I would love to see
your results.
Clear skies!
Anthony.
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Date: 02 Jul 2007 10:36:18
From: Themos Tsikas
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
That's it! When I retire it will be in Greece! On the western slopes
of Dirfys, Evia, I think.
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Date: 02 Jul 2007 19:16:09
From: Anthony Ayiomamitis
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
Themos Tsikas wrote:
> That's it! When I retire it will be in Greece! On the western slopes
> of Dirfys, Evia, I think.
>
Themi,
There will be the annual national star party on Dirfy next month ... I
think it is around July 20-22/2007.
Anthony.
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Date: 21 Jun 2007 16:38:59
From:
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
On Jun 21, 5:18 am, Anthony Ayiomamitis <anth...@perseus.no2spam.gr >
wrote:
> Dear Group,
>
> With Cygnus slowly getting into good position for imaging, there is a
> wide variety of goodies it provides for the interested observer and imager.
>
> Given the plethora of Barnard dark nebulae it offers, I thought I would
> try my hand with one of the largest such objects just north of the
> bright star Sadr.
>
> More specifically, I pursued B343 which lies within a couple of degrees
> just north of Sadr. For an image based on four hours total exposure, I
> kindly direct you tohttp://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm. This is my first
> attempt at a dark nebula and I would welcome all feedback. I have
> checked around and cannot find any reference images for comparison B343
> ... if someone has pursued this particular object, I would love to see
> your results.
>
> Clear skies!
>
> Anthony.
Great looking image and those dark nebula take plenty of exposure time
too. The web address I provide here is of the Ha region with Sadr in
the lower right hand corner. This was a total of 90 minutes in Ha and
45 minutes total in RGB with a FSQ106n and ST-2000 camera at Palomar
Mountain last year. I plan to return this year with a ST10XME and re-
shot that area for more detail and a little large field of view.
http://www.vistaobservatory.com/image%20gallery/Nebula/NGC6910LRGBweb.gif
Enjoy!
OPTwebman
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Date: 28 Jun 2007 00:22:37
From: AstroApp
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
On Thu, 21 Jun 2007 16:38:59 -0700, john@optcorp.com wrote:
>Great looking image and those dark nebula take plenty of exposure time
>too. The web address I provide here is of the Ha region with Sadr in
>the lower right hand corner. This was a total of 90 minutes in Ha and
>45 minutes total in RGB with a FSQ106n and ST-2000 camera at Palomar
>Mountain last year. I plan to return this year with a ST10XME and re-
>shot that area for more detail and a little large field of view.
>
>http://www.vistaobservatory.com/image%20gallery/Nebula/NGC6910LRGBweb.gif
>Enjoy!
>OPTwebman
John,
Exquisite image! I appreciate seeing the link to your site, my first
experience with it.
I take it, if I am assuming right, that you are the webmaster for the
site given in the link above. I tried to contact the site using the
webpage but with either Firefox or IE, the "contact" page comes up
with no information, just a large empty turquoise-colored box.
In fact, to get that page, I had to paste the link to it into the
browser, since the inline links to "contact" at the BOTTOM of the
pages don't work (though the ones at the top left column do work; more
on this below.)
So, I have a couple of comments about the site that perhaps I could
address to you via this post of yours to saa.
First, I noticed that all your pictures are GIFs. I checked the Gum 1
nebula picture IC2177LRGBweb.gif and -- yes -- it has only 255 colors.
You could probably get better color accuracy with JPG format, which
has a palette of millions of colors.
Second, the file size of that picture is nearly 900kB. As a test, I
compressed it about 84% to a JPG and the size shrank to something
around 54kB; a tiny amount of detail was lost but one can play with
the compression and come up with something quite effective, and still
be much smaller than 900k -- AND contain more color info.
Third, the webpage of Images uses these huge GIFs but shrinks them
down by scaling their size in the HTML code; the entire files have to
load -- even if you don't click on any of them to see them full sized
-- which, in my case, meant a HUGE long wait just to get the page. If
you use thumbnails (JPGs preferably) you can probably make each of
those small pictures no more than 20k and the page will come up MUCH
faster; then when you click the thumbnail, the full large scale file
will load.
Fourth, the menu of info at the bottom of each page has a consistent
HTML error. The links for all but the home page are incorrect and do
not point to the file on your server, but to C: drive. Therefore, on
MY computer the links for "About", "Our Services", "Related Links",
and "Contact" will not come up; instead my browser gives a "file
error" saying that there is no such file. Of course it's due to the
HTML code. I have pasted in the source code from your page, below, so
that you can see what it says:
<p ><a href="index.html">Home</a> - <a
href="file:///C
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Date: 28 Jun 2007 00:41:47
From: AstroApp
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
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John, a small correction of what I said, about IC2177LRGBweb.gif:
>Second, the file size of that picture is nearly 900kB.
I was mistaken about 900 kB, as I took this information from the NEXT
picture, the Horsehead nebula, below it. The actual file size that I
downloaded of Gum 1 was 192k, which is almost four times the size of
the file that resulted when I made a JPG version with mild
compression. So *apologies* for misreading and mis-reporting the
original file size.
Still, 192kB is an awfully large size for one picture file that is
only 600x450 pixels. The file sizes of astronomical pictures that
size on most websites will indeed be much smaller, in JPG format,
perhaps half to a quarter the file size of a comparable GIF.
On your images page, just to bring up those thumbnails the following
data must completely download into the user's browser:
IC2177LRGBweb.gif - 192 kB
IC434LRGBweb.gif - 910 kB
M20LHRGBweb.gif- 985 kB
M17LRGBweb.gif - 813 kB
NGC6334LRGBweb.gif - 579 kB
NGC6910LRGBweb.gif - 1336 kB
NGC7380LRGBweb.gif - 779 kB
NGC281LRGBweb.gif - 414 kB
NGC2264LRGBweb.gif - 1493 kB
I think that with small, compressed JPG thumbnails the size you desire
(160x120) you can cause the browser to load no more than about 90 to
100 kB, rather than a whopping several MEGABYTES of file data in order
just to show the thumbnails.
You can write the HTLM code so that when one clicks on the thumbnail,
then the full sized file loads and opens...
Best,
Srw
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Date: 28 Jun 2007 00:44:11
From: AstroApp
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
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On Thu, 28 Jun 2007 00:41:47 GMT, AstroApp
<Astro-App@not-receiving-email.com > wrote:
>You can write the ****HTLM**** code so that when one clicks on the thumbnail,
>then the full sized file loads and opens...
Attention, pedants:
Typo, of course! :-)
Srw
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Date: 22 Jun 2007 18:19:33
From: Anthony Ayiomamitis
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
john@optcorp.com wrote:
> On Jun 21, 5:18 am, Anthony Ayiomamitis <anth...@perseus.no2spam.gr>
> wrote:
>
>>Dear Group,
>>
>>With Cygnus slowly getting into good position for imaging, there is a
>>wide variety of goodies it provides for the interested observer and imager.
>>
>>Given the plethora of Barnard dark nebulae it offers, I thought I would
>>try my hand with one of the largest such objects just north of the
>>bright star Sadr.
>>
>>More specifically, I pursued B343 which lies within a couple of degrees
>>just north of Sadr. For an image based on four hours total exposure, I
>>kindly direct you tohttp://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm. This is my first
>>attempt at a dark nebula and I would welcome all feedback. I have
>>checked around and cannot find any reference images for comparison B343
>>... if someone has pursued this particular object, I would love to see
>>your results.
>>
>>Clear skies!
>>
>>Anthony.
>
>
> Great looking image and those dark nebula take plenty of exposure time
> too. The web address I provide here is of the Ha region with Sadr in
> the lower right hand corner. This was a total of 90 minutes in Ha and
> 45 minutes total in RGB with a FSQ106n and ST-2000 camera at Palomar
> Mountain last year. I plan to return this year with a ST10XME and re-
> shot that area for more detail and a little large field of view.
>
> http://www.vistaobservatory.com/image%20gallery/Nebula/NGC6910LRGBweb.gif
Thanks John. Great image.
Anthony.
>
> Enjoy!
> OPTwebman
>
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Date: 21 Jun 2007 16:31:06
From: Ben
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
On Jun 21, 11:36 am, "Paul Clark" <dr.cl...@dial.pipex.com > wrote:
> Hi Anthony
>
> I'm not a fan of diffraction spikes, especially when they turn red :)
Hi Anthony,
I rather like diffraction spikes regardless of color.
> However, it is a very, very nice image with great subtle detail. I must
> have looked at this area and overlooked this DN many times visually :(
I have viewed it several times. It stands out right easily
against
IC 1318 in the background.
> Looking forward to more. I find that looking for DN brings out the detail
> in the surrounding area alot more.
6888 is only a couple of degrees South. Are you going to try it?
It's a splendid but difficult object. Anyway your capture of B 343 is
just ominous.
Ben
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Date: 22 Jun 2007 18:17:50
From: Anthony Ayiomamitis
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
Ben wrote:
> On Jun 21, 11:36 am, "Paul Clark" <dr.cl...@dial.pipex.com> wrote:
>
>>Hi Anthony
>>
>>I'm not a fan of diffraction spikes, especially when they turn red :)
>
>
> Hi Anthony,
Hi Ben,
> I rather like diffraction spikes regardless of color.
It is one of those things which you either like or dislike. There seems
to be little middle ground. I also do like them as well.
>
>
>>However, it is a very, very nice image with great subtle detail. I must
>>have looked at this area and overlooked this DN many times visually :(
>
>
> I have viewed it several times. It stands out right easily
> against
> IC 1318 in the background.
Ditto here ...
>
>
>>Looking forward to more. I find that looking for DN brings out the detail
>>in the surrounding area alot more.
>
>
> 6888 is only a couple of degrees South. Are you going to try it?
In fact I took some test exposures about ten days ago in h-alpha ... WOW!
> It's a splendid but difficult object. Anyway your capture of B 343 is
> just ominous.
I expect a very nice result with the Crescent Nebula. I suspect I will
pursue it aggressively a few days after full moon (this lunation) since
it has been a "to-do" item for some time (similar to the Bubble Nebula
in Cas which will have to wait a bit) and I have a good idea of my
exposure times for both h-alpha and RGB.
Back at it again this evening for another Barnard dark nebula. :-)
Anthony.
>
> Ben
>
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Date: 21 Jun 2007 17:36:03
From: Paul Clark
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
Hi Anthony
I'm not a fan of diffraction spikes, especially when they turn red :)
However, it is a very, very nice image with great subtle detail. I must
have looked at this area and overlooked this DN many times visually :(
Looking forward to more. I find that looking for DN brings out the detail
in the surrounding area alot more.
Regards
Paul
"Anthony Ayiomamitis" <anthony@perseus.no2spam.gr > wrote in message
news:f5dqbv$j4r$1@mouse.otenet.gr...
> Dear Group,
>
> With Cygnus slowly getting into good position for imaging, there is a wide
> variety of goodies it provides for the interested observer and imager.
>
> Given the plethora of Barnard dark nebulae it offers, I thought I would
> try my hand with one of the largest such objects just north of the bright
> star Sadr.
>
> More specifically, I pursued B343 which lies within a couple of degrees
> just north of Sadr. For an image based on four hours total exposure, I
> kindly direct you to http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm
> . This is my first attempt at a dark nebula and I would welcome all
> feedback. I have checked around and cannot find any reference images for
> comparison B343 ... if someone has pursued this particular object, I would
> love to see your results.
>
> Clear skies!
>
> Anthony.
>
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Date: 21 Jun 2007 13:30:58
From: Sam Wormley
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
Anthony Ayiomamitis wrote:
> Dear Group,
>
> With Cygnus slowly getting into good position for imaging, there is a
> wide variety of goodies it provides for the interested observer and imager.
>
> Given the plethora of Barnard dark nebulae it offers, I thought I would
> try my hand with one of the largest such objects just north of the
> bright star Sadr.
>
> More specifically, I pursued B343 which lies within a couple of degrees
> just north of Sadr. For an image based on four hours total exposure, I
> kindly direct you to
> http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first
> attempt at a dark nebula and I would welcome all feedback. I have DWB41 & B343
> checked around and cannot find any reference images for comparison B343
> .... if someone has pursued this particular object, I would love to see
> your results.
>
> Clear skies!
>
> Anthony.
>
I found this interesting image of DWB41 & B343 with poorer resolution than
your excellent image, Anthony.
http://www.andreasroerig.de/g2/dwb041.htm
http://www.andreasroerig.de/g2/dwb041.jpg
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Date: 21 Jun 2007 17:20:23
From: Anthony Ayiomamitis
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
Sam Wormley wrote:
> Anthony Ayiomamitis wrote:
>
>> Dear Group,
>>
>> With Cygnus slowly getting into good position for imaging, there is a
>> wide variety of goodies it provides for the interested observer and
>> imager.
>>
>> Given the plethora of Barnard dark nebulae it offers, I thought I
>> would try my hand with one of the largest such objects just north of
>> the bright star Sadr.
>>
>> More specifically, I pursued B343 which lies within a couple of
>> degrees just north of Sadr. For an image based on four hours total
>> exposure, I kindly direct you to
>> http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my
>> first attempt at a dark nebula and I would welcome all feedback. I
>> have DWB41 & B343
>> checked around and cannot find any reference images for comparison
>> B343 .... if someone has pursued this particular object, I would love
>> to see your results.
>>
>> Clear skies!
>>
>> Anthony.
>>
>
> I found this interesting image of DWB41 & B343 with poorer resolution
> than
> your excellent image, Anthony.
> http://www.andreasroerig.de/g2/dwb041.htm
> http://www.andreasroerig.de/g2/dwb041.jpg
>
>
Thanks Sam! The fellow strictly used h-alpha which confirms my
suspicion about needing the same. In fact I have the same h-alpha filter
he used and which I will put into use (probably this evening).
To the rescue once again. :-)
Anthony.
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Date: 21 Jun 2007 10:43:09
From: George
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
"Anthony Ayiomamitis" <anthony@perseus.no2spam.gr > wrote in message
news:f5e1fp$ltd$2@mouse.otenet.gr...
> Sam Wormley wrote:
>
>> Anthony Ayiomamitis wrote:
>>
>>> Dear Group,
>>>
>>> With Cygnus slowly getting into good position for imaging, there is a
>>> wide variety of goodies it provides for the interested observer and
>>> imager.
>>>
>>> Given the plethora of Barnard dark nebulae it offers, I thought I would
>>> try my hand with one of the largest such objects just north of the
>>> bright star Sadr.
>>>
>>> More specifically, I pursued B343 which lies within a couple of degrees
>>> just north of Sadr. For an image based on four hours total exposure, I
>>> kindly direct you to
>>> http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my
>>> first attempt at a dark nebula and I would welcome all feedback. I have
>>> DWB41 & B343
>>> checked around and cannot find any reference images for comparison B343
>>> .... if someone has pursued this particular object, I would love to see
>>> your results.
>>>
>>> Clear skies!
>>>
>>> Anthony.
>>>
>>
>> I found this interesting image of DWB41 & B343 with poorer resolution
>> than
>> your excellent image, Anthony.
>> http://www.andreasroerig.de/g2/dwb041.htm
>> http://www.andreasroerig.de/g2/dwb041.jpg
>>
>>
>
> Thanks Sam! The fellow strictly used h-alpha which confirms my suspicion
> about needing the same. In fact I have the same h-alpha filter he used
> and which I will put into use (probably this evening).
>
> To the rescue once again. :-)
>
> Anthony.
I'd be interested in seeing your result when you are done.
George
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Date: 21 Jun 2007 08:59:34
From: George
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
"Anthony Ayiomamitis" <anthony@perseus.no2spam.gr > wrote in message
news:f5dqbv$j4r$1@mouse.otenet.gr...
> Dear Group,
>
> With Cygnus slowly getting into good position for imaging, there is a
> wide variety of goodies it provides for the interested observer and
> imager.
>
> Given the plethora of Barnard dark nebulae it offers, I thought I would
> try my hand with one of the largest such objects just north of the bright
> star Sadr.
>
> More specifically, I pursued B343 which lies within a couple of degrees
> just north of Sadr. For an image based on four hours total exposure, I
> kindly direct you to
> http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first
> attempt at a dark nebula and I would welcome all feedback. I have checked
> around and cannot find any reference images for comparison B343 ... if
> someone has pursued this particular object, I would love to see your
> results.
>
> Clear skies!
>
> Anthony.
Nice. Here is one I found on google images:
http://www.masil-astro-imaging.com/FTP/B343-HARGB-2.jpg
I hope this helps.
George
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Date: 21 Jun 2007 17:18:13
From: Anthony Ayiomamitis
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
George wrote:
> "Anthony Ayiomamitis" <anthony@perseus.no2spam.gr> wrote in message
> news:f5dqbv$j4r$1@mouse.otenet.gr...
>
>>Dear Group,
>>
>>With Cygnus slowly getting into good position for imaging, there is a
>>wide variety of goodies it provides for the interested observer and
>>imager.
>>
>>Given the plethora of Barnard dark nebulae it offers, I thought I would
>>try my hand with one of the largest such objects just north of the bright
>>star Sadr.
>>
>>More specifically, I pursued B343 which lies within a couple of degrees
>>just north of Sadr. For an image based on four hours total exposure, I
>>kindly direct you to
>>http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first
>>attempt at a dark nebula and I would welcome all feedback. I have checked
>>around and cannot find any reference images for comparison B343 ... if
>>someone has pursued this particular object, I would love to see your
>>results.
>>
>>Clear skies!
>>
>>Anthony.
>
>
> Nice. Here is one I found on google images:
>
> http://www.masil-astro-imaging.com/FTP/B343-HARGB-2.jpg
Thanks George! It confirms my suspicion that the result needs some H-a
data to improve the luminance portion.
>
> I hope this helps.
It certainly does and I thank you!
Anthony.
>
> George
>
>
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Date: 21 Jun 2007 10:42:34
From: George
Subject: Re: B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
|
"Anthony Ayiomamitis" <anthony@perseus.no2spam.gr > wrote in message
news:f5e1bn$ltd$1@mouse.otenet.gr...
> George wrote:
>> "Anthony Ayiomamitis" <anthony@perseus.no2spam.gr> wrote in message
>> news:f5dqbv$j4r$1@mouse.otenet.gr...
>>
>>>Dear Group,
>>>
>>>With Cygnus slowly getting into good position for imaging, there is a
>>>wide variety of goodies it provides for the interested observer and
>>>imager.
>>>
>>>Given the plethora of Barnard dark nebulae it offers, I thought I would
>>>try my hand with one of the largest such objects just north of the
>>>bright star Sadr.
>>>
>>>More specifically, I pursued B343 which lies within a couple of degrees
>>>just north of Sadr. For an image based on four hours total exposure, I
>>>kindly direct you to
>>>http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first
>>>attempt at a dark nebula and I would welcome all feedback. I have
>>>checked around and cannot find any reference images for comparison B343
>>>... if someone has pursued this particular object, I would love to see
>>>your results.
>>>
>>>Clear skies!
>>>
>>>Anthony.
>>
>>
>> Nice. Here is one I found on google images:
>>
>> http://www.masil-astro-imaging.com/FTP/B343-HARGB-2.jpg
>
> Thanks George! It confirms my suspicion that the result needs some H-a
> data to improve the luminance portion.
>
>>
>> I hope this helps.
>
> It certainly does and I thank you!
>
> Anthony.
>
>>
>> George
De nada.
George
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