[gregbradley]

I asked Don from Astrodon whether 3nm Ha is the way to go with my new AP Riccardi Honders scope.

He said I would be better off staying with the 5nm as 3nm blocks N11 and the 5nm does not unless I was imaging in a light polluted area in which case the 3nm was the way to go.

As far as was 3nm OK with F3.8 he said yes it was.

I remember Berts Honders 3nm Ha images that had a lot of grainy grit background black clipped look and I was not sure if that was his processing error or from the filters. It looked badly black clipped. Still not sure but the 5nm Ha from Astrodon I have been using (just replaced it with a new one because of a chip) is sensational at a dark site with smooth backgrounds fairly quickly and terrific detail.

3nm may be good for things like planetary.

Greg.