Steve et al,
To record the filaments and prominences you need a solar H alpha filter.
Unfortunately these are MUCH more expensive than white light filters.
A very cost effective alternative is one of the 3D printed "Sol'Ex" mini spectroheliographs.
This allows you to image in any visible wavelength - Calcium, Magnesium, Sodium, Hydrogen etc etc.
Check out the forum and Christian's website.
https://groups.io/g/Solex-English
http://www.astrosurf.com/solex/sol-e...uction-en.html