Explore Scientific 1.25″ OIII Nebula Filter
The 1.25″ OIII Filter by Explore Scientific is a line filter, allowing only the two emission lines of oxygen to pass through. This filter is a fantastic choice for exploring supernova remnants and other nebulae that glow in OIII. When used on objects that glow in all parts of the visible spectrum, such as galaxies, this filter dims all emissions except for oxygen. In other words, some areas will suffer from the addition of an OIII filter, while other areas that may normally be difficult to see will become visible when viewed through the OIII filter.
The Explore Scientific 1.25″ OIII Filter has a transmission of 96.7% from 483nm to 511nm. Peak transmission is 496nm. This filter is mounted in a 1.25″ metal cell and fits all standard 1.25″ eyepieces and filter wheels.