NGC 672 and IC 1727

Objects: NGC 672 (center), 11.5m, 7.2' x 2.6', SB(s)cd spiral galaxy, and IC1727 (upper left), 12.1m, 6.9'x3.1', SB(s)m, in Triangulum.

Subimages L: 23 x 300 sec (1.9 hrs), Input FWHM = 2 - 3.1", Final FWHM=2.7"
Subimages RGB: 6/8/9 x 300s binned 2x2, Final FWHM=3.3/3.4/3.9"
Scope: C11XLT EFL=1657 mm (f/6 effective)
Mount: Losmandy G11 with Gemini L4
Camera: ST8XME+CFW10 (1.12"/pixel) set to -20C
Guiding: Self-guide, ExpTime=1s L, 2s RGB, dithered
Acquisition and processing: MaxIm DL/CCD v4.5
Imaged on: Sept 20, 22, 2007

3rd place in 2007 SCT-User Imaging Contest for Best Deep Sky Image with Astronomical Camera. Many thanks to organizer Rod Molisse and sponsor Robert Piekiel who donated a copy of his book on CD "Celestron The Early Years". See this site for all the contest entries.

Processing Log

00XC: Combine: SDmask, linear; autostarmatch
00XRGB: Combine: SDmask, linear; autostarmatch

00XC-fbgd: bgd flatten manual 31pts
00XC-fbgd-rb: remove bloom, auto
00XC-fbgd-rb-crop: crop 40,30-1450,970
00XRGB-a-crop: dblsize; aligned to L frame; crop 40,30-1450,970
00XRGB-a-crop-fbgd: 36/45/49 pts
00XRG-a-crop-fbgd-rb: remove bloom, auto
00XRGB-a-crop-fbgd-beq: 726/1020/758.5
00XC-fbgd-rb-crop-beq: 1615
00X-Lab: Lab combine of beq files with auto bgd, 1:1.022:1.259, Lweight=100%
00X-Lab-ddp: bgd=65, mid=700, no filter
00X-Lab-ddp-clnX: many iterations of clone of kfilter/cbal copies
00X-LR: converted to 16bit int, CCDSharp 5 target stars, 4 iterations
00X-LR-Lab: as above
00X-LR-Lab-ddp: bgd=65, mid=700, no filter
00X-LR-Lab-ddp-lvl: boost red black level, reduced blue/green white levels, white level started at 42121 adu
00X-LR-Lab-ddp-lvl-crop: 100,0 x 1270,970
00X-LR-Lab-ddp-lvl-crop-clnX: copied stars from a gblurred version, used r=2 gblur for 3 brightest, g=1 for fainter stars, also used range resriction on gblur (6800+, Rr=1, Fd=3)