STC Astro-Multispectra filter is a general-purpose light pollution suppression filter designed to use with DSLRs cameras. It will effectively reduce the interference from artificial lighting, such as mercury and sodium street light, yet allow the important nebula emission lines to pass, thus enhancing the contrast of astronomical objects. Supporting by Dr. Wei-Hao Wang, it is improved to passing more than 95% of the light from the main spectral lines from emission nebula, such as the predominant Hydrogen-Alpha line at 656.3nm, the Oxygen III line at 495.9 & 500.7nm, and the Hydrogen-Beta line at 486.1nm. It is coated by the use of the IBAD (Ion beam-assisted deposition) technology on Schott® B270 optical glass, working for higher durability and easily cleaning. Since light pollution and airglow are filtered out with ASTRO filter, much more of the interesting wavelengths of the deep-sky object will be recorded in these longer exposures.
|Available Size||48, 77 mm, Clip Filter|
|Metrial||SCHOTT® B270 Optical Glass, Aluminum 6061 rim|
|Thickness||2mm glass, 3.5mm rim|
|Weight||12g(Ø: 48mm)/29g(Ø: 77mm)|
|Depth of CS||20~35μm (350MPa)|
|Water drop contact angle||＞110°|
|Multiple coating||Both-sided, Total 160 layers|