ZWHA7NMD2

HA7NMD2

ZWO

This 2" ZWO 7nm Narrowband Ha Filter can help your observation and photography of spectacular emission nebulae. The filter passes hydrogen-alpha light at 656nm, resulting in photos with high contrast. The filter also reduces artificial light like streetlights and natural but unwanted light caused by neutral oxygen emission in the earth's atmosphere. The filter's cell is 5mm thick plus 2.5mm of M48 x 0.75 male thread. The glass filter itself is 1.85mm thick.