Astrophotography by Keith B. Quattrocchi

NGC 891
Edge On Spiral Galaxy in Andromeda
LRGB Image

Copyright 2008
Keith B Quattrocchi

Image Acquisition Information                      
 
Telescope: 16" RCOS Richey Chretien Telescope (ion milled at 6/9) 
Camera: SBIG STL-6303 M
Guiding: SBIG AOL, Astrodon  MOAG AOG (SBIG 237 with FLR)
Filters: Astrodon L, R, G, B, Ha, SII, OIII
Mount: Software Bisque Paramount ME
Acquisition Programs:  The Sky,CCDAutopliot III, CCD Soft. 
Processing Programs: CCDStack, Maxim DL, Photoshop
Date: September 30 -October 20, 2008                              
Time: 15x20 min ( 5 hours) each for each of L, R, G, B:
Total of 20 hours imaging time.                              
Processing:  CCD Stack and PhotoShop CS/3
 
Image Infornmation:  LRGB image of NGC 891 in Adromeda.  This is a relatively faint 13' x 2.8' edge on spiral galaxy known for it's faint dust lane and the unusual 'vertical' (aiming away from the central regions)filamentary nebular patterns.  The vertical filaments are thought to be due to a supernova or other catastophic event.  The galaxy  is about 30 million light years distant. 
 
Additional Comments:  The image was first assebled as an RGB object in CCDStack.  In order to avoid star halos, the DDP option was not used and the image stretched manually ('maximum' right/'gamma' left and then decreased background to avoid clipping).  The RGB and luminance layers were assembled in Photoshop CS3 (normal mode).  A second layer of the galaxy core, enhancing the filamentary patterns, was layered onto this composite.  Further data stretching, high pass filtering and background smoothing was performed with Adobe Photoshop CS/3.