(Click on image for full size version)
|Description:||This group of galaxies consists of NGC7331, the
large one, and on the left from top to bottom, NGC7335, NGC7336, NGC7340
(left) and NGC7337(right). Reportedly,
Tomm Lorenzin (author of
"1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing") gave the
name to the NGC 7331 group in honor of Deer Lick Gap in the mountains of
North Carolina where he observed and once had an especially fine view of the
group of galaxies.
|Exposure Data:||9/13,18/2003. LRGB: 8x10m, 4x10m,
4x10m, 4x10m. RGB 2x2. -10°C, 0.74 arc-sec./pixel.
|Processing:||Acquired via Sequencer and CCDSoft, reduced and
aligned, in Mira, RL 2x CCDSharp, RGB combine and DDP in Maxim, LRGB combine, curves, levels and other
processing in Photoshop.
|Optical System:||12.5” Ritchey-Chretien RCOS Truss @ F/6,
CCD camera, Paramount ME. AO7 guided
|Comments:||Luminance obtained by dither tracking of the
AO7, using a development version of Sequencer. Here is a link to the
full size and
reduced size image without
dithering. Also here is an
introduction to dithering techniques along with a zoomed and cropped
comparison of the luminance image. Here
is a link to the focal reducer arrangement used.