Re: [APML] Winter Milky Way

["Chris Cook" <ccjd@ix.netcom.com>]

Wow!!!!
The sky background does look a bit brown, but as you mentioned, it could be
because you are working off a backup monitor.

The Mauna Kea sky must be so amazing.  Is there any difference to the sky
darkness at the 9200' visitor center compared to the summit region?  I would
think hypoxia would have an effect at the summit?

Chris

----------------------------------
Chris Cook
Astronomical & Nightscape Photography
www.abmedia.com/astro

-----Original Message-----
From: Wei-Hao Wang <whwang@asiaa.sinica.edu.tw>
To: Discussion of Film Astrophotography <astro-photo@seds.org>
Date: Monday, January 12, 2004 8:32 PM
Subject: [APML] Winter Milky Way


>ALOHA,
>
>I finish the FIRST processing of my winter Milky Way mosaic.  I'm not
>too confident of the results.  Probably the best version still need
>a few more iterations.
>
>It's in
>http://www.ifa.hawaii.edu/~wang/gallery/picutres/WinterMilkWay2003.htm
>
>I had sent this picture to a Japanese magazine.  Let me
>copy the comments to the editors here:
>
>1. This is a mosaic of 10 pictures.  Nine of them form the base 3X3
>mosaic.  An extra one centered at Orion was stacked onto the base
>to improve the signal-to-noise ratio of this region.
>
>2. All 10 images were taken under excellent atmospheric transparency.
>
>3. Vignetting pattern of the optics was removed by my own written
>program.  Distortion correction and initial color match were done in
>Registar.  Sky background removal, final color match, and mosaicing
>were done in PhotoShop.  Except for tone curve changes, no further
>image processing was applied.
>
>4. Due to the light pollution, zodiacal light, and scattered car
>light, the sky background in each of the 10 frames is very different
>and nonuniform.  The vignetting correction and the removal of these
>unwanted lights are challenging.  I was worrying that some artificial
>feature (or in other words, "fake nebulas") will appear because of the
>inaccurate vignetting correction.  By comparing with previous pictures
>and the original slides, I believe some uncommon faint features in
>this picture are "real."  These include:
>  a) the wide and faint blue nebulas around M45 and above Alpha Tau.
>  b) the red north-south elongated nebula between Taurus and Eridanus,
>     which I believe to be Sh2-39.
>  c) a faint blue nebula to the right (west) of the Witch Head Nebula.
>  d) the color of the Milky Way between IC450 and the California Nebula
>     becomes a little green.
>
>Any comments are welcome.
>
>Because my monitor was broken a few days ago, I'm using a backup monitor
>which may not be well calibrated.  If you feel the color very
>uncomfortable, this might be the reason.
>
>Wei-Hao
>
>_______________________________________________
>Astro-Photo mailing list
>Astro-Photo@seds.org
>http://seds.org/mailman/listinfo/astro-photo
>

_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo