Narrowband Imaging

NGC 2359 Thor's Helmet, HaOIIIOIII

Date: April 3, 2008

Telescope: Celestron 8 XLT f/2 on CGE mount

Camera: Starlight Xpress SXV-H9C

Exposure: 12 5-min subframes (60 min total) each Ha and OIII guided with Meade DSI pro and piggybacked Meade DSX-90 at f/13.8 using PHD Guiding.

Comments: HyperStar 3 lens, Astronomik 13nm Hydrogen alpha filter. Only red channel of the H9C camera used. Astronomik 13nm Oxygen III filter. Only green channel of the H9C camera used.