It's a fascinating subject and a great idea in principle, but as OIC points out, the band of nighttime filters is WAY too broad to show any detail. In fact, the band required is so narrow that the radial speed of prominences/filaments can sometimes render them invisible in a proper h alpha filter due to doppler shift. Tuning the filter to get them back into view is part of the fun observing the most dynamic object accessible to earth bound telescopes. Also the amount of appropriate-wavelength light that the eyesight-preserving and therefore essential white light filter in your setup passes through is ridiculously small, so even if you had a very narrow band filter at the other end, there wouldn't be much left to work with.
In short - if it worked, almost everybody would be doing it. The spectacular views of the star would ensure that.
There is an exciting alternative avenue, which may one day be one of my ATM DIY projects: A spectrohelioscope.
http://spectrohelioscope.org/page2.htm
http://www.cornellcollege.edu/physic...elioscope.html
I have never looked through one, but they seem to be marvellous devices. Look at the sketch of the solar disk in the first link. I have no idea why the likes of GSO aren't already churning these out. I reckon narrow band solar observing -and NOT limited to h alpha - would be accessible to even a modest budget. Going by the components used by the DIYers, they could be priced at well below $500. It may be one of the next great developments in the world of astro instruments.
Edit: Consider this related subject:
http://spaceweathergallery.com/indiv...pload_id=96189
This is so unbelievably good that I will not comment any further.