I have had an OIII filter for years. Never use it.
I can never see anything through it. I once looked at a star with it and all I saw was a faint red dot - totally useless.
What are you supposed to use them on?
Itis a Lumicon Nebula line transmission %
Oxygen 496 nm 93
Oxygen 501 nm 93
Hydrogen beta 486 nm 0.4
What does that all mean???
