Optolong SII 3nm CCD 2" Filter
Optolong SII 3nm CCD 2" Filter
The SII (Sulfur II) CCD filter is an extra narrowband filter designed for nebula observation. The SII filter from Optolong allows a 3nm bandwidth of light centered on a wavelength of 672 nm though. Like the OIII and the H-alpha filters, the SII filter reduces transmission of certain light wavelengths, particularly those that are produced by artificial light and natural light/sky glow.
Adding this SII (Sulfur II) CCD filter to your astrophotography setup will give you higher contrast, greater detail, decreased background noise, and increased faint nebula signal. It corresponds with the RGB channel, allowing imagers to process Hubble images with post-processing astrophotography software.
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.