Optolong H-Alpha 3nm CCD 2" Filter
Optolong H-Alpha 3nm CCD 2" Filter
The Optolong H-Alpha 3nm filter is a popular narrowband filter that allows a 3nm bandwidth of light centered on a wavelength of 656nm to pass through while reducing the transmission of certain wavelengths of light, specifically those produced by artificial light such as mercury vapor, high and low pressure vapor lights, and unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e.skyglow). For maximum contrast and revealing subtle nebula details, use a narrowband H-Alpha astrophotographer filter.
Optolong SHO-3nm Narrowband Filters Performance
As we all know, the OIII narrow band filter has always been a halo problem. The halo of the OIII 3nm filter was optimized by optimizing the coating technology, based on the experience of the 7nm narrow band filter.
About Optolong
Optolong is the Astronomy Filters division of Yulong Optics, an optical filter design and processing company out of Kunming, China that has provided filters for over 700 optical companies since 1999. All Optolong filters pass European Union RoHS requirements and have been certified by TUV Rheinland and Bureau Veritas.