Filters SII 7nm 2"

Sii filters: The narrow-band filter allows light from ionised sulphur atoms at 671.7 and 673.1 nanometres to pass through. These are the lines in which many planetary nebulae, emission nebulae and supernova remnants shine.

Astrophotography: Monochromatic cameras are best for this. Ideally, you should combine shots with sii, oii and h-alpha filters. This will give you an image that shows the delicate nebula structures clearly and with high contrast.