Nebula filter

Characteristic:
Improved contrast for nebula
Aperture : 44mm(2 inch) 24mm(1.25inch)
Thread measurement : M48*0.75

Specification:
High Transmittance in H-Alpha(656.3nm), H-Beta(486nm), O III(496nm and 501nm) : >90%
Low Transmittance in 436nm(Hg), 546nm(Hg), 589nm(Na), 620nm(Hg) (Light pollution) : <2%

Curve:

coming soon