Coronado Solarmax III 10mm Blocking Filter - 624015

The Coronado BF10 is a 10mm right angle diagonal type Hydrogen-alpha blocking filter. It includes a long 2" diameter nosepiece with 1.25" eyepiece holder and 42mm t-thread connection.

The BF10 is named because of the 10mm clear aperture window that passes the hydrogen-alpha light to the eyepiece or camera sensor. It provides a full disc image of the Sun for telescopes up to 1000mm in focal length. As the size of the clear window increases (BF15, BF30) the larger the field of view and the longer your telescope's focal length can be and still get a full disc image.

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, which is not included. The BF10 cannot be used without the etalon in place.