The Antlia H-Alpha ultra narrow-bandfilters boost the contrast of emission nebulae and supernova remnants for professional results, even under a bright sky affected by light pollution.
The3.5nmband pass is only 1% of the entire visible spectrum, increasing the signal to noise ratio and delivering high contrast images and extremely dark backgrounds. To even further enhance the contrast, and suppress the stray light and internal reflections, Antlia appliesedge-blackeningcoating on each filter.
The maximum transmission of the Hydrogen Alpha line (656.3 nm) is above90%and the transmission off band is only0.1%. This is a value often undisclosed by other filter producers and it is critical to darken the sky background and minimise the halos around the stars.
Each filter is individuallytestedto ensure a high quality standard. The tight tolerance of the filters substrate assure a maximum deviance of±0.05from specifications making these filters parfocal.
The filter cuts off the ultraviolet and infrared light so there is no need to use the IR-cut filter.