This OIII filter particularly enhances planetary nebulae in larger telescopes.
Narrowband filter for high transmission, with high blocking of unwanted longer wavelengths to yield high-contrast images.
Ion beam technology and optical glass produces low scatter in a hard stable coating to reduce changes due to temperature and humidity.
Optical quality ground and polished BK7 glass yields sharp star images - even when filter is placed in front of diagonal.
100% quality control: