Sharpless 91 - Nebula in Hydrogen Alpha
Sh2-91 H-Alpha

Sh2-91 in H-Alpha [click on the image to see it 2x]
Camera: Apogee U16M 
Filter: Astrodon 5nm Gen II H-Alpha 
Scope: AP155 F7 w 4" FF
Exposure: 32 x 15 minutes = 8 hours
Flesherton, Ontario, Canada
Oct 2011
Ambient temp 10C; camera temp -20C; Moon was waxing
Images captured using CCDSoft5
Images calibrated (darks and flats), aligned and sigma-reject combined in Maxim
Contrast / Brightness adjustments, Levels in Photoshop CS4