Do you enjoy observing mysterious nebulae such as the Veil Nebula or the Owl Nebula with your telescope? If you are a lover of deep sky objects, then a variety of deep sky filters are almost a must-have accessory. Using these filters, you can study in particular the details of planetary nebulae or supernova remnants that you would not see without a filter, or only from a very dark sky.
The Explore Scientific OIII filter is a special deep sky filter. Its principle of operation is quite simple: it only passes certain wavelengths of incoming light, precisely those at which the objects above are emitting. Specifically, only the emission lines of excited state oxygen reach our eyes, all other wavelengths are "cut off" by the filter. As a result, the contrast between the sky background and the object being observed increases spectacularly, the fog almost pops out of the sky background, making faint details visible.
Of course, the filter can also be used from the city: it helps to combat stray background light caused by light pollution. However, they are not a substitute for dark skies, which means that if you are aiming to observe faint deep sky objects, it is definitely worth taking your binoculars under a dark, rural sky. OIII filters transmit less light than UHC filters, so are recommended primarily for telescopes 20 cm or larger.
Each Explore Scientific deep sky filter is uniquely tested by the manufacturer, and a certificate is issued. Premium quality is thus guaranteed.