NGC 7293 -- The Helix Nebula I

The famous Helix Nebula in Aquarius -- at only 7000 lightyears distance, this 2.5 lightyear diameter planetary nebula fills our 14x21' FOV.

Processing was by 3 different methods. The first, shown here, used a luminance layer consisting of the Ha and OIII data, superimposed on an RGB layer in which Ha was added to the Red, and OIII was added to both the Green and Blue channels. RGB star data was then overlayed. This method portrays the Helix as we are used to seeing it -- dominated by the Ha emission.

However, the second version of the Helix emphasizes the OIII emission, and can be found here.

The third version is a modified bicolor image, using only the Ha nd OIII data, and can be found here.