Filters Johnson B 1,25"

The frame allows the filter to be attached to a connector, a filter holder or in the housing of a camera.

A standard measurement for accessories, expressed as 1.25 inches. 1.25" is equal to 31.8 millimetres.

The optical elements are treated with ultra-thin coatings. Among others, there are anti-reflective coatings for reducing, and dielectric coatings for increasing reflection.

No matter whether they are for observing or for astrophotography, filters are very important accessories.