- Hydrogen-alpha blocking filter for Coronado primary etalon filters
- Secondary interference filter for full disc image of the Sun for telescopes up to 1,000mm focal length
- Long 2" diameter nosepiece with 1.25" eyepiece holder and t-thread
- 10mm clear aperture provides a wider unvignetted field of view compared with the smaller BF5 filter
- MUST be used in conjunction with a front etalon filter - cannot be used alone
The Coronado BF10 10mm right angle (diagonal) type Hydrogen-alpha blocking filter, now in the SolarMax III design! This updated design includes a long 2" diameter nosepiece with 1.25" eyepiece holder and t-thread connection. The blocking filter is the second element in any Coronado H-alpha system, and is just as crucial to your safety and the system's performance as the primary SolarMax etalon filter. Note this blocking filter CANNOT be used without a SolarMax etalon in front of the telescope front aperture. This secondary interference filter provides a full disc image of the Sun for telescopes up to 1,000mm focal length. Can be used with 1.25" focusers by purchasing the Coronado 1.25" adapter #624018.
The BF10 is named because of the 10mm clear aperture window that passes the hydrogen-alpha light to the eyepiece or camera sensor. This 10mm window is wider than the window in the BF5, and thus provides a wider unvignetted field of view around the sun. This will allow wider apparent field of view eyepieces, higher magnification, and larger camera sensors to see an unvignetted view compared with the BF5 version.
Designed and Manufactured in North America.