Had a short window last night between clouds.
This is only four frames of four minutes each taken with 3nm NII filter.
These objects seem to have about the same if not a bit more of NII versus HA. NII is a forbidden transition of Nitrogen and needs hot or very hot blue stars to produce it.
The HA filter is 3nm wide centered on 656.3 nm. The NII filter is also 3nm wide and centered on 658.4 nm. Any HA filter that is wider than about 5nm actually picks up both these transitions. It should be interesting down the track to see what objects have very different distributions of H and N.
Below is a diagram from Astrodons site.
Here is the large image at full resolution 6MB
http://d1355990.i49.quadrahosting.co...7&6334_NII.jpg
Once I get the guiding etc sorted will do much longer exposures.
Bert