Instrument

12.5" RCOS @  ~f/9 (2880 mm fl) 0.643 arcsec / pixel.  The Zoomify image scale is 0.94 to 2.31 arcsec / pixel.

Mount

Paramount ME

Camera

SBIG STL-11000 w/ internal filter wheel, AstroDon Filters

Acquisition Data

11/18/2009 to 11/22/2009 Chino Valley, AZ... with CCDAutoPilot3 & CCDSoft.

Exposure

Lum    270 min (18 x 15 min, bin 1x1)

RGB    315 min (  7 x 15 min each, bin 2x2)

Software

CCDSoft, CCDStack, Photoshop CS w/ the Fits Liberator plugin and Russell Croman's GradientXTerminator and Noel Carboni's actions.

Noel Carboni's StarSpikes Pro was used to restore and sharpen the normal spider defraction spikes.

PixFix32 (pre-beta) to repair hot/cold pixels and column defects.

CCDStack to calibrate, register, normalize, data reject, combine the sub exposures & RGB color.

PhotoShop for LRGB combine &  on-linear stretching.

North is to the top.

The planetary nebula, NGC 246, is 1,600 light-years away in the constellation Cetus. Appropriately named, "the Skull Nebula" it was formed by expelled gasses of the outer atmosphere of a once sun-like star. The central star is the fainter of a binary system and is entering its final phase of becoming a white dwarf.