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View Full Version : ASTRO: Widefield North American Nebula/Pelican/IC5068 in [SII], Ha and [OIII]


Richard Crisp
January 2nd 04, 10:06 PM
here are two different palettes used for the Na Nebula/Pelican IC5068
complex.

http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm

This is widefield shot of 9 square degrees taken with a horribly
undersampled FLI Dream Machine used on an AP Traveler with a 0.75x
telecompressor. The effective focal length was close to 475mm which results
in a plate scale of 10.5 arc-sec/pixel.

Focusing was a bit challenging but I got "close enough" to see what the area
looks like.

Probably I will re-shoot in higher resolution this year.

News
January 3rd 04, 01:25 PM
is there supposed to be an image on this link?


> http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>

Chosp
January 4th 04, 01:01 AM
"News" > wrote in message
...
> is there supposed to be an image on this link?
>
>
> > http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
> >
>

There is - and it is quite a good one.

Stefan Lilge
January 4th 04, 03:48 PM
Richard,

neat image, lots of signal. With the colours you gave it it looks a bit like
an aurora :-)

Stefan

"Richard Crisp" > schrieb im Newsbeitrag
m...
> here are two different palettes used for the Na Nebula/Pelican IC5068
> complex.
>
> http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>
> This is widefield shot of 9 square degrees taken with a horribly
> undersampled FLI Dream Machine used on an AP Traveler with a 0.75x
> telecompressor. The effective focal length was close to 475mm which
results
> in a plate scale of 10.5 arc-sec/pixel.
>
> Focusing was a bit challenging but I got "close enough" to see what the
area
> looks like.
>
> Probably I will re-shoot in higher resolution this year.
>
>
>

Richard Crisp
January 4th 04, 08:13 PM
Thanks for the comment Stefan. The colors are a fall-out from using the
filters I did. The [SII], Ha and [OIII] set only capture those specific
emission lines and then I assemble them into a tricolor.

One way to assign the colors is strictly by wavelength: the longest
wavelength gets Red, the next shorter gets Green and the shortest wavelength
gets Blue. That would correspond to the image just below.

http://www.rdcrisp.darkhorizons.org/images/NGC7K_IC5070_IC5068_S2HaO3.jpg I
call that palette the "Pillars Palette" because that is the color palette
used by the Hubble team that took that wondeful shot of the core of M16.
Same filters too.

The other way I combine them is to assign Ha to Red (sort of familiar from
the visual world), [OIII] to Green (again, kind of familiar from the visual
world) so that leaves [SII] being used for Blue. Here is the image that
results from that assignment:

http://www.rdcrisp.darkhorizons.org/images/NGC7K_IC5070_IC5068_HaO3S2.jpg
I call that Palette the "CFHT Palette" because that is what they did with
their Rosette Nebula:

http://www.rdcrisp.darkhorizons.org/ngc2244_rosette_cfht_page.htm


Best wishes for the new year folks!
Richard



"Stefan Lilge" > wrote in message
...
> Richard,
>
> neat image, lots of signal. With the colours you gave it it looks a bit
like
> an aurora :-)
>
> Stefan
>
> "Richard Crisp" > schrieb im Newsbeitrag
> m...
> > here are two different palettes used for the Na Nebula/Pelican IC5068
> > complex.
> >
> > http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
> >
> > This is widefield shot of 9 square degrees taken with a horribly
> > undersampled FLI Dream Machine used on an AP Traveler with a 0.75x
> > telecompressor. The effective focal length was close to 475mm which
> results
> > in a plate scale of 10.5 arc-sec/pixel.
> >
> > Focusing was a bit challenging but I got "close enough" to see what the
> area
> > looks like.
> >
> > Probably I will re-shoot in higher resolution this year.
> >
> >
> >
>

Richard Crisp
January 5th 04, 01:26 AM
Last night I was blessed with another clear night. There was a lot of moon
and it was up high most of the night, but I was using Ha and [OIII] filters
so I wasn't too worried about it; I was just happy to have a clear sky after
all the rain we've had recently.

I took some more data for the Cone project and began taking some exposures
of Thor's Helmet in Ha and [OIII].

I did not get but one hour's worth of Ha for Thor but did assemble it into a
sample shot: sort of an early look-see at what may be in store.

http://www.rdcrisp.darkhorizons.org/ngc2359_thor_page.htm

I used my Dream Machine exposed through a Custom Scientific 3nm Ha filter.
The scope was my C14. I used and AO7/ST7 for guiding via an RCOS Optical
Systems Dichroic Beam Splitter.

The C14 is running about f/12.46 with the long imaging train hanging off the
back. At that slow focal ratio, I was running 20 minute exposures and took
three, which were median combined to make the image.

More results when they become available.

Richard

Martin C Germano
January 6th 04, 02:01 AM
> I did not get but one hour's worth of Ha for Thor but did assemble it into
a
> sample shot: sort of an early look-see at what may be in store.

I like that one Richard ... very reminiscent of a Tech Pan image.

-- Marty

Martin C Germano
http://home.earthlink.net/~mcgermano

George Normandin
January 6th 04, 02:45 AM
"Richard Crisp" <> wrote

> here are two different palettes used for the Na Nebula/Pelican IC5068
> complex.
>
> http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>
> This is widefield shot of 9 square degrees taken with a horribly
> undersampled FLI Dream Machine used on an AP Traveler with a 0.75x
> telecompressor. The effective focal length was close to 475mm which
results
> in a plate scale of 10.5 arc-sec/pixel.........

That's a very interesting pair of images Richard! Have you tried
'narrow-band' filters and a full spectrum Luminance image?

For such wide-field images I think your image scale is just fine. I've
used a ST-6 on an 80mm Brandon triplet and I'm happy with the results. You
might get more resolution using the DRIZZLE method, but I'm not sure that it
would matter much considering the fine results you already have.

George Normandin

Richard Crisp
January 6th 04, 01:53 PM
"Martin C Germano" > wrote in message
hlink.net...
> > I did not get but one hour's worth of Ha for Thor but did assemble it
into
> a
> > sample shot: sort of an early look-see at what may be in store.
>
> I like that one Richard ... very reminiscent of a Tech Pan image.
>
> -- Marty
>
> Martin C Germano
> http://home.earthlink.net/~mcgermano
>
>

Thank you Marty, What a nice comment from the "king of Tech Pan". Let me
tell you that you have been a guiding light in getting me interested in this
hobby. I've seen your images for years and they were always pulling me to
just do it. Finally in late 2000 I decided to buy a telescope and what a
wonderful adventure it has been.

Thank you very much for the comment. It means a lot to me.
Best regards,
Richard

Stefan Lilge
January 6th 04, 09:54 PM
Richard,

beautiful image. Looks like the skull of some strange animal.

Stefan

Richard Crisp
January 6th 04, 11:42 PM
"George Normandin" > wrote in message
...
>
> "Richard Crisp" <> wrote
>
> > here are two different palettes used for the Na Nebula/Pelican IC5068
> > complex.
> >
> > http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
> >
> > This is widefield shot of 9 square degrees taken with a horribly
> > undersampled FLI Dream Machine used on an AP Traveler with a 0.75x
> > telecompressor. The effective focal length was close to 475mm which
> results
> > in a plate scale of 10.5 arc-sec/pixel.........
>
> That's a very interesting pair of images Richard! Have you tried
> 'narrow-band' filters and a full spectrum Luminance image?

No I have not done that. One thing I have done is to combine (sum) the three
emission line band data and use that for luminance.

>
> For such wide-field images I think your image scale is just fine. I've
> used a ST-6 on an 80mm Brandon triplet and I'm happy with the results. You
> might get more resolution using the DRIZZLE method, but I'm not sure that
it
> would matter much considering the fine results you already have.
>
> George Normandin


Those images were really intended more as "survey" images: I get 9 square
degrees and can shoot three shots of five minutes each through each of five
filters and get an image done in a bit more than an hour. That lets me
decide what objects are "interesting" and warrant a more detailed
examination later. I was shooting four such tricolor survey images per night
when I did these back in October.

Turns out some of the images were pretty good as is. That surprised me.

Martin C Germano
January 7th 04, 02:22 AM
Richard,

> Thank you very much for the comment. It means a lot to me.

I'm blushing <g>! Thanks for your kind comments ... I have been 'following'
your recent work from your posts on the APML. Those narrow band false color
images are very impressive ... and you can do them from a light polluted
area! Outstanding work!

-- Marty

Martin C Germano
http://home.earthlink.net/~mcgermano

Bill Meyers
January 7th 04, 04:37 AM
Hello, Martin C. Germano,
I am glad to see you posting here. Stay with us.
I have admired your astrophotos for many years, several decades in fact.
Very fine work. If
Your web page is very helpful and informative.
Clear skies,
Bill Meyers

Martin C Germano wrote:

> > I did not get but one hour's worth of Ha for Thor but did assemble it into
> a
> > sample shot: sort of an early look-see at what may be in store.
>
> I like that one Richard ... very reminiscent of a Tech Pan image.
>
> -- Marty
>
> Martin C Germano
> http://home.earthlink.net/~mcgermano
>

Richard Crisp
January 7th 04, 02:41 PM
"Martin C Germano" > wrote in message
hlink.net...
> Richard,
>
> > Thank you very much for the comment. It means a lot to me.
>
> I'm blushing <g>! Thanks for your kind comments ... I have been
'following'
> your recent work from your posts on the APML. Those narrow band false
color
> images are very impressive ... and you can do them from a light polluted
> area! Outstanding work!
>
> -- Marty
>
> Martin C Germano

Again thanks, Marty.

From my perspective once I got started using the emission line filters, they
are sort of the only option from a light polluted suburban backyard. It
seems like all I otherwise do is to try to remove gradients.

Two tradeoffs: slower exposures, weird colors.

on the former, the big pixels and high QE of the Dream Machine helps with
exposure length. On the latter, I have sort of tired of red objects and sort
of welcome a new set of colors. Besides those colors seem fine coming from
the Hubble, so why not?

Best regards
Richard

News
January 8th 04, 12:44 AM
not for this user there isn't

Chosp wrote:
> "News" > wrote in message
> ...
>
>>is there supposed to be an image on this link?
>>
>>
>>
>>>http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>>>
>>
>
> There is - and it is quite a good one.
>
>

Trane Francks
January 8th 04, 02:18 AM
On 01/08/04 09:44 +0900, News wrote:

> not for this user there isn't
>
> Chosp wrote:
>> "News" > wrote in message
>> ...
>>
>>>is there supposed to be an image on this link?
>>>
>>>
>>>
>>>>http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>>>>
>>>
>>
>> There is - and it is quite a good one.

His images are some of my favourite and this link
(NGC7000/IC5070/IC5068 Widefield) is absolutely stunning. If you
can't see things, you should check your browser. Ya gots ta be
able to see frames.

trane
--
//------------------------------------------------------------
// Trane Francks Tokyo, Japan
// Practice random kindness and senseless acts of beauty.

Martin C Germano
January 8th 04, 02:31 AM
Bill,

> I am glad to see you posting here. Stay with us.

I've been reading and occasionally posting here for years ... just seems
like *most* of what goes on here is not 'up my ally'.

-- Marty

Martin C Germano
http://home.earthlink.net/~mcgermano

News
January 8th 04, 02:32 AM
netscape 7.1??? oughta work...BUT IT DOESN'T

Trane Francks wrote:
> On 01/08/04 09:44 +0900, News wrote:
>
>> not for this user there isn't
>>
>> Chosp wrote:
>>
>>> "News" > wrote in message
>>> ...
>>>
>>>> is there supposed to be an image on this link?
>>>>
>>>>
>>>>
>>>>> http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>>>>>
>>>>
>>>
>>> There is - and it is quite a good one.
>
>
> His images are some of my favourite and this link (NGC7000/IC5070/IC5068
> Widefield) is absolutely stunning. If you can't see things, you should
> check your browser. Ya gots ta be able to see frames.
>
> trane

News
January 8th 04, 02:34 AM
oh by the way, other links from this site do have work for me

Trane Francks wrote:

> On 01/08/04 09:44 +0900, News wrote:
>
>> not for this user there isn't
>>
>> Chosp wrote:
>>
>>> "News" > wrote in message
>>> ...
>>>
>>>> is there supposed to be an image on this link?
>>>>
>>>>
>>>>
>>>>> http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
>>>>>
>>>>
>>>
>>> There is - and it is quite a good one.
>
>
> His images are some of my favourite and this link (NGC7000/IC5070/IC5068
> Widefield) is absolutely stunning. If you can't see things, you should
> check your browser. Ya gots ta be able to see frames.
>
> trane

Trane Francks
January 8th 04, 07:23 AM
On 01/08/04 11:32 +0900, News wrote:

> netscape 7.1??? oughta work...BUT IT DOESN'T

Works here with Netscape 7.1, Konqueror 3.1.4 and Galeon 1.3.9. I
have no idea why you'd have trouble (but I haven't taken the time
to examine the page source, either).

trane
--
//------------------------------------------------------------
// Trane Francks Tokyo, Japan
// Practice random kindness and senseless acts of beauty.

Odysseus
January 8th 04, 10:32 AM
News wrote:
>
> netscape 7.1??? oughta work...BUT IT DOESN'T
>
<http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm>

Seems fine from here, using Netscape 4.78, and also with Opera 5.

--
Odysseus

Chosp
January 8th 04, 02:37 PM
"News" > wrote in message
...
> not for this user there isn't

It works for me on:
Mozilla, Netscape 4.72, Netscape 7.0, Internet Explorer 5.0
All work just fine.
Don't know what else to say.

>
> Chosp wrote:
> > "News" > wrote in message
> > ...
> >
> >>is there supposed to be an image on this link?
> >>
> >>
> >>
> >>>http://www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068_page.htm
> >>>
> >>
> >
> > There is - and it is quite a good one.
> >
> >
>

Richard Crisp
January 8th 04, 02:38 PM
"News" > wrote in message
...
> oh by the way, other links from this site do have work for me


Try this one that has no frames:

www.rdcrisp.darkhorizons.org/ngc7k_ic5070_ic5068.htm


I am sorry that you are having troubles.

By the way, I have tried three times to actually post the binary jpg inline
but it is not making out best I can tell. I am puzzled by that.

Richard