Optical FIlter Astronomy 656.3 Ha 10nm 1.25" Eyepiece

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Check out my other items!

This filter is designed for Amateur Astronomers desiring to capture the emission of SII from Nebula and Galaxies. The filter transmits efficiently the emission at 656.3nm of Hydrogen Lyman Alpha (80 to 90%) while rejecting most other light. This filter has a free spectral range from the UV to NIR (most light from 200 to 1000nm is attenuated to 10e-3 avg, so it can be used with a CCD camera, as well as film. Due to the eyes insensitivity, this filter is not suitable for visual observation.

The filter size is a nominal 26mm, and is mounted in a threaded 28.5mm standard eyepiece mount. This size is often referred to as 1.25.".

Filter specifications follow:

CWL 656.3+-1nm, HBW 9+-2nm, Transmission >80% at CWL, Blocking Avg 10e3 from 200 to 1000nm. (limited transmission to OD 1.0 may occur with negligible impact on performance.) Mounted in standard eyepiece mount of 48mm size.

If you don't find what you want with a simple search in my BJOMEJAG EBUYER STORE, try a wild card search by using an asterisk after the wavelength.

If you are still not finding a good match, follow my links to Omega's Build a Filter. With a note to the effect that cosmetic seconds are acceptable, you will be surprised how economical an exact match can be.

For much more information on interference filters and their applications please visit my blog at www.bjomejag.squarespace.com/ . If you have ideas for additional topics to elaborate on, do leave a note.