| |
Main
Date: 23 Aug 2007 13:50:07
From: William R. Mattil
Subject: [s.a.a] Finally some clear nights ! M27 in LHaRGB
|
All,
The Spring Monsoons lingered halfway through the summer this year and
after literally 4 months without a clear night an all too brief period
of clearing occurred so I grabbed the following image. Still not ideal
as there was some thin haze but the seeing was quite good.
M27 - LHaRGB image 5x600 sec (LRGB) 3x1800sec (Ha) Ha data combined with
L and R before Color Combine. Tracking was excellent over the course of
this but keeping up with the focus shift was still an issue. I think
that the focus could have been improved but having been so long without
a usable night I jumped the gun and started before the optics were at
ambient.
There was still some high thin haze that presented some challenges in
processing. But the Moon wasn't a factor.
http://www.celestial-images.com/Images/M27-5x600s-LHaRGB.html
Regards
Bill
|
|
| |
Date: 23 Aug 2007 17:29:19
From: ko57
Subject: Re: Finally some clear nights ! M27 in LHaRGB
|
> Hi Kerry,
>
> Thanks for the comments. M27 actually is quite bright and I think you
> should be able to see it. On top of the 10 inch Ritchey I have a FSQ106N
> mounted and it *is* visible in that. Not markedly so mind you. But I
> think this is one instance where a fast Refractor might be advantageous.
> My skies are terrible, maybe Mag 3.5 or 3.8 overhead and the Horizon is
> useless. so hopefully that gives you something to gauge your chances by.
> Usually planetary nebulae are better subjects due to their small size vs
> brightness.
>
> Best Regards
>
> Bill
My skies are right at 3.8-4, sometimes a bit darker, but still I just
can't make it out. Even though the moon is up tonight I might still
give it a try, but I'll definitely give it another go when the moon
disappears again. I read somewhere that a black observing blanket
helps for this, I have a black piece of material somewhere that I
could use, might help.
I'm going back & forth on filters, either a Lumicon Deep Sky or maybe
an Orion Ultrablock or Lumicon UHC. Seems I read everywhere that the
UHC is better, except for Laura's Deep sky recommendation, and as much
as David Knisely recommends the UHC over all as far as nebulas, he did
mention broadbands like the Deep Sky has it's merits for other things
like galaxies. I had tried Astronomik's UHC, I didn't find it helped
much, gave the sky an unnatural looking red/pink tint, I preferred the
Orion Nebula (easy to see) without it.
I can find M57 with no problem.
Clear skies (and no monsoons for you Bill)
Kerry
|
| |
Date: 23 Aug 2007 13:36:05
From: ko57
Subject: Re: Finally some clear nights ! M27 in LHaRGB
|
That's great-M27 is one object I cannot see. I guess the few
floodlights nearby contributes enough to overall skyglow-doesn't help
me out one bit. >:( I'll wait until the moon disappears and try
again, couldn't see it last year no matter what. I guess it's time to
get a filter...I'd read Laura Halliday's post where a Lumicon
broadband filter did well for M27. While it might be hard to compare
my skies to hers, she seemed to enjoy the results with that filter on
a few objects:
http://groups.google.com/group/sci.astro.amateur/browse_frm/thread/6ee594fb957e2653?hl=en
Nice shot, Bill...
Clear skies,
Kerry
|
| | |
Date: 23 Aug 2007 15:55:27
From: William R. Mattil
Subject: Re: Finally some clear nights ! M27 in LHaRGB
|
ko57 wrote:
> That's great-M27 is one object I cannot see. I guess the few
> floodlights nearby contributes enough to overall skyglow-doesn't help
> me out one bit. >:( I'll wait until the moon disappears and try
> again, couldn't see it last year no matter what. I guess it's time to
> get a filter...I'd read Laura Halliday's post where a Lumicon
> broadband filter did well for M27. While it might be hard to compare
> my skies to hers, she seemed to enjoy the results with that filter on
> a few objects:
> http://groups.google.com/group/sci.astro.amateur/browse_frm/thread/6ee594fb957e2653?hl=en
>
>> Nice shot, Bill...
>
Hi Kerry,
Thanks for the comments. M27 actually is quite bright and I think you
should be able to see it. On top of the 10 inch Ritchey I have a FSQ106N
mounted and it *is* visible in that. Not markedly so mind you. But I
think this is one instance where a fast Refractor might be advantageous.
My skies are terrible, maybe Mag 3.5 or 3.8 overhead and the Horizon is
useless. so hopefully that gives you something to gauge your chances by.
Usually planetary nebulae are better subjects due to their small size vs
brightness.
Best Regards
Bill
|
|
