Chroma SII 8nm Narrow Band Filters are essential for imaging objects, like nebulae, that are rich in ionized sulfur atoms. These line emission filters work extremely well in heavy light-polluted areas and allow you image on nights when the moon is up.

• Parfocal for systems f/4.0 or slower
• Transmitted wavefront better than 0.25 waves/inch
• Parallelism: less than 30 arcsec
• Made in the U.S.A.
• H-Alpha 8nm Narrow Band Filter