Coronado Solarmax III 30mm Blocking Filter - 624017

The Coronado BF30 is a 30mm 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. This blocking filter, which is Coronado's largest available, can be converted to straight-through mode with the included adapter. 

The BF30 is named because of the 30mm 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 3000mm in focal length. This 30mm blocking filter is a great choice for those who want to use large camera sensors, do high magnification work, or use eyepieces with wider apparent fields of view/.  

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 BF30 cannot be used without the etalon in place.