We have it fairly easy with simple H alpha filters these days. The original Spectroheliograph was more complicated and needed to form an image on film by scanning the image of the sun across a slit. It's an interesting device that is not needed these day. Of course if you want to get complicated there is always a Lyot filter.
We have it fairly easy with simple H alpha filters these days. The original Spectroheliograph was more complicated and needed to form an image on film by scanning the image of the sun across a slit. It's an interesting device that is not needed these day. Of course if you want to get complicated there is always a Lyot filter.