The SVBONY 7nm dual band filter is designed to drastically reduce the effect of light pollution. The 7nm bandwidth means it strongly isolates the nebulae's emissions into H-Alpha (red) and OIII (green-blue) from anything else. It blocks light pollution, maximizes the signal from nebulae, and darkens the sky background. It also blocks artificial light from mercury vapor lamps, high- and low-pressure sodium vapor lights, and unwanted natural light caused by the emission of neutral oxygen in our atmosphere.

Features:
1.Dual Narrow bandwidth H-Alpha/O-III 7nm narrowband filter properly designed for astrophotography both in light polluted
2.Allows for imaging in bright man-made light pollution and moonlit conditions
3.Take color images without needing to combine images with multiple filters
4.Most useful for One-Shot Color cameras
5.Useful for imaging emission nebulae, planetary nebulae and supernova remnants
6.High transmission and sharp cut-off can greatly enhance the contrast and bring out the most detailed information for those deep-sky objects
7.Designed to sharply cut off the inference of artificial light from sodium vapor or mercury vapor street lights and other unwanted disturbance like sky glow
8.The duo-band narrowband filter is not suitable for visual observation and not designed for imaging or observing the Sun
9.Be aware that the SV220 is not a great fit for fast telescopes, some users reported that the Duo-Band OSC Filter paired with the RASA caused band shift, thus clipping the HA data.