In addition to the turbulence in the air, the brightening of the night sky is the greatest obstacle to observing faint objects beyond the solar system. Street lights and other artificial lighting mean that the sky in human settlements is no longer properly black. As a result, the contrast and thus the perception of the deep-sky objects also suffer. Depending on the type of celestial object, however, part of the interfering light can be filtered out, thus making it easier to photograph the objects.
The Explore Scientific H-Alpha filter uses the property of the so-called emission mist. These objects glow in certain colors, the so-called emission lines. The emission lines are linked to certain chemical elements - in this case the red glowing hydrogen. This filter blocks all other colors (and thus almost all artificial light) and only lets through the emission lines of the hydrogen. In particular, the disruptive light from mercury and sodium vapor lamps is effectively blocked. The effect is amazing: Suddenly fog becomes visible in the photos in places that appear completely empty without a filter.
The Explore Scientific H-alpha mist filter has been developed exclusively for astrophotography. Especially when the sky is slightly brightened, many emission nebulae only come to light when this filter is used and are shown in full extent on the astrophotos. The H-alpha nebula filters make astrophotography near cities possible and their use leads to surprisingly good image results despite the existing light pollution. A must for every urban astrophotographer.
The Explore Scientific mist filters are supplied with an individual test report - so you can be sure that you are receiving high-quality filters.
CA Residents: Prop 65 WARNING(S)
