Sh2-155 aka Caldwell 9 aka The Cave Nebula

The Cave aka Caldwell 9 aka Sh2-155

The Cave Nebula in Cepheus

The Cave Nebula, Sh2-155 or Caldwell 9, is a dim and very diffuse bright nebula within a larger nebula complex containing emmison, reflection, and dark nebulosity. [Wikipedia]

STL11000 w Astronomik RGB and 6nm H-Alpha filters
AP155 EDF F/7 w Robofocus
H-Alpha: 13 x 30 min self-guided on an AP900GTO mount
RGB: 9x10min Red, 8x10min Green and Blue
Acquired with CCDSoft5
Additional hot pixel removal and column repair in CCDOps
Darks, Flats, Alignment and Sigma Reject combine in Maxim
Levels and Curves in CS4
Noel's Tools used to remove vertical bars from readout noise (I think)

Click on the image to see it 1.5x this resolution and to resize it in the browser.

Click HERE to see the H-Alpha only channel.

Flesherton, Ontario
Nov 7/8/11 2009