Baader Semi-APO Filter - Round Mounted - FSAPO- 15 mm Eyepieces Less than 1% shrinkage or

Less than 1% shrinkage or stretch assures continuous proper fit

Secondary Mirror Obstruction by Area: 14 %

Baader Contrast Booster Filter Specifications

Camera Control port

Explore Scientific 30mm 82 Degree Series Waterproof Telescope Eyepiece - 2" Features

Baader Semi-APO Filter - Round Mounted - FSAPO- 15 mm Eyepieces Less than 1% shrinkage orAbout the Baader Semi APO Filter Round Mounted The Baader Planetarium Semi APO Filter works like it'''s name implies, delivering an amazingly neutral view, while cutting most of the annoying and contrast robbing violet fringe that plagues all achromats. The Semi APO filter combines a stronger Fringe Killer coating formula with the Moon & Skyglow Neodymium substrate. The result is similar performance to the Fringe Killer plus Moon & Skyglow