[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
Re: [APML] New Ha(Ha/R,GB) Images
Dear Brian,
Both of these images are great! The one of NGC 7635 also shows
color-selective diffraction spikes, probably a good reason to find a
way to remove them. But that's just my perfectionist's opinion,
which counts for nothing compared to the work you've put into these
great shots!
Paul Rybski
>Hi All,
>
>Hope you all are having a great holiday season!
>
>I'm kind of a season behind with these objects but with a few days
>off I finally got
>to them. These 2 images are wide field (38 x 25 arc minutes) CCD images of the
>Bubble and Crescent Nebulas using HaRGB compositing techniques. The
>Crescent is a
>rework that I posted a few months back but the star colors and
>nebulosity are much better.
>The HaRGB technique was tricky to get good color results. Each image
>is 120:30:30:30
>minute respective exposure using a 20" f/4 homemade Newt and a
>Finger Lakes IMG6303E
>CCD camera. The Ha and R channels were combined 50/50 to make the R
>component for
>the RGB color composite. The image scale is 1.5 arcsec/pixel.
>
>Following the thread of digital vs film......with the 1 & 1/2 hour
>of download time ( parallel
>interface on my camera) for these series of images it now takes 5
>hours of acquisition time
>to just get the raw data for one of these images. A few years back
>short exposure times
>were touted as a main advantage for CCD imagers but as we have
>gained experience
>exposures are now at or exceeding film length times to get optimum
>results not to mention
>the post processing times involved.
>
>
>These new images are at:
>
>http://www.heavensgloryobservatory.com/Color_Jpegs/ngc6888HaRGB08-6303Eweb.jpg
>
>and
>
>http://www.heavensgloryobservatory.com/Color_Jpegs/ngc7635HaRGB03-6303Eweb.jpg
>
>
>
>Best regards, Brian Lula
>
>
>
>
>Brian Lula
>Polytec PI, Inc.
>(508) 832-3456
>
>-- APML Archives at <http://astro.umsystem.edu/apml/> ---
> Unsubscribe at <majordomo@seds.org>
________________________________________
Paul M. Rybski, Ph.D.
Associate Professor and Acting Chair, Dept. of Physics, and
Director, Whitewater Observatory
Goodhue 320
University of WI-Whitewater
Whitewater, WI 53190-1790
Office FAX: (262) 472-5633
Email address: rybskip@uww.edu
-- APML Archives at <http://astro.umsystem.edu/apml/> ---
Unsubscribe at <majordomo@seds.org>