Baader Dark Blue 435nm Bandpass Filter - Round Mounted - FCFDB- 2" Filters Effective Field Stop: 9

Effective Field Stop: 9

called using averted vision

" -Ray Khan

then sand blasted and anodized to protect from harsh environment

regardless of the number of elements

Baader Dark Blue 435nm Bandpass Filter - Round Mounted - FCFDB- 2" Filters Effective Field Stop: 9Choose either the Baader 1. 25" or 2" Dark Blue 435nm Bandpass Filter from the dropdown About the Baader Dark Blue 435nm Bandpass Filter Baader Planetarium astronomy filters by far supersede the mediocre quality of common "flame polished" color filters. A fine optical polish and 2 mm thick glass allows the Baader Dark Blue Filter to be inserted anywhere into the optical path without introducing astigmatism or other defects. For instance, they can be