NGC 7317-7320 - Arp 319 - Hickson 92


Object: NGC 7317-20: galaxies in Pegasus, 5 components: NGC 7317 (bottom right) type E4 13.6m 1.1'x1.1', NGC 7318a (middle right) E2 pec. 14.5m 0.9'x0.9', NGC7318b (middle left) SB(s)bc pec 14.2m 1.9'x1.2', NGC 7319 (top left) SB(s)bc pec 13.3m 1.7'x1.3' and NGC 7320 (bottom left) (R)SAB(s)0/a 13.3m 1.9'x1.1'.

Subimages: 22 x 600s (3.7 hrs) SD Mask combined after bias, dark and flat calibration. Input FWHM 2.3"-3.4", output 3".
Scope: C11XLT with C6.3FR, EFL=1589mm (f/5.7 effective)
Mount: Losmandy G11 with Gemini L4
Camera: ST7EI (1.17"/pixel) set to -25C oriented at 3d28' (N up, E left)
Guiding: SX716 camera on a Taurus Tracker III OAG. Exposure time 1 sec.
Acquisition and Processing: MaxIm DL/CCD v4.5
Imaged on: Nov 23-24, 2006

Processing:
No background flattening required since flat-fielding worked extremely well.
Did not use L-R deconvolution, it had a tremendous effect on galaxy detail however too many embedded stars showed Gibb's rings.
Remove Bloom: 2nd brightest star, it also needed edit pixels after DDP.
DDP: bgd=1590, mid=2000, filter Kernel LowPassMore.
Crop: Removed brightest star (bloomed) and seam from multi-night imaging.