Helix nebula

This photo was taken on 2013/11/13 with a modified Canon 450D with one polution filter and a Sky Watcher 200/1000 telescope. Guided with Celestron and a Meade DSI
30 lights of 120" at ISO 400; 30 darks; 30 flats and 30 offsets.
Named also NGC 7293, this planetary nebula is located in Acuarius, 680 lights year to the sun. Ap. mag.:13,5; Absolute diameter: 5,74 ly.