Re: [APML] What lies beneath M78

["Mike Cook, AF9Y" <mwcook@concentric.net>]

Thanks Loke,

    Your question about the weak magenta area at the top of your 
M78 CCD image is what prompted me to look at adding Ha.  In
this direction, my skies are about a 4 mag.  I'm only about 6 miles
north of Ft. Wayne, IN.  That makes the southern objects a real
challenge.  Even Ha imaging takes extra exposures to bring the
S/N up.  Blue takes about 4 times as much even with the LPF.

Mike

>From:           	"tan@home.com" <tan@home.com>
>
> Mike,
> 
>  Very interesting shot. This image is picking up quite a bit of h-alpha in 
> the upper right half. I have been wondering how real this red region was 
> in my widefield Schmidt shot at
> 
> http://www.starryscapes.com/nebula/barnards_loop_n.html
> 
> The 6 hours for h-alpha and 4 for RGB is really long. How dark are your 
> skies? I presume the light pollution does not hurt the h-alpha much at 
> all since it is so narrowband.
> 
> Loke
> 
> 
> 
> 
> 
> Mike Cook, AF9Y wrote:
> 
> > After seeing the Gendler and Loke postings of M78, I was
> > inspired to see how deep one could go to show the background
> > structure surrounding this area.  Using a 4 hour Ha base and
> > 6 hours of RGB the background is beginning to show even
> > from my driveway with very polluted southern skies:
> > 
> > http://www.webcom.com/af9y/m78hrgb.htm
> > 
> > The upper right edge of this image shows the very weak
> > outer edge of Barnard's loop as it ripples into the reflection
> > area surrounding M78.  The colors are not spectacular with
> > the weak Ha showing a more of a magenta hue as it mixes
> > with the reflection nebula and background sky.
> > 
> > 
> > 
> > Mike Cook, AF9Y
> > http://www.webcom.com/af9y
> > mwcook@cris.com
> > 
> > 
> > 
> > 
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Mike Cook, AF9Y
http://www.webcom.com/af9y
mwcook@cris.com




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