A fabulous image. Your 14.25 RCOS is awesome.
On the topic of what colour Ha really is, there was a very informative post where I started a thread on Astromart.
Here it is:
http://tinyurl.com/4zrrqj
One point about deciding that Ha must be dark red because the filter looks very red when put up to a white light- the Astrodon type mirror filters look odd colours when you look at them. For example the red filter initially looks blue and the blue filter looks orange as it is reflecting unwanted wavelengths.
Per the article it shows Ha as red and lower emission lines as deep red. So perhaps plain ole red is correct after all.
Greg.