Lunt Blocking Filter B500 in 1.25" star diagonal

Only Lunt Blocking Filters make the H-alpha observation possible and protect from dangerous radiation.

Lunt Solar Systems currently offers different blocking filter apertures for use with their H-alpha etalon systems. The blocking filters are absolutely required for the safety and performance of telescopes for solar observing! Blocking filters will be mounted at the eyepiece-side of the telescope, and protect against the dangerous radiation from the sun.

We are currently offering the B600d, B1200d, and B1800d in a 90° star diagonal, with 1.25" or 2" on the telescope side, and T2 (M42x0.75) and 1.25" on the eyepiece side.

The B600s, B1200s, and B1800s is also being offered in a straight through extension tube with T2 on both sides, 1.25" or 2" on the telescope side, and 1.25" on the eyepiece side. The extension tube of the B3400s has a 2" connection on the telescope side, and a 2" receptacle and adapter for 1.25" eyepieces on the other side.

The Blocking Filter B500 is for maximum focal length 500 mm.

[*Lunt Solar Systems blocking filters contain a unique filter system. We can only warranty safety or performance if the blocking filter is paired with an original H-alpha front filter of Lunt Solar Systems.

Important hint: In humid air, blocking filters might tarnish, so keep yours dry. You can get little packages of silica gel for reducing humidity even more. Put one and the filter into a small freezer bag and seal it.