The 2" 7nm H-Alpha filter from Explore Scientific is specially designed for astrophotography and allows capturing emission nebulae, even under skies polluted by artificial light. This filter blocks almost all other colors, allowing only the emission lines of hydrogen, which shine in red, to pass through. It effectively eliminates disturbing light from mercury and sodium vapor lamps, revealing details invisible to the naked eye. With a narrow bandwidth of only 7nm, this filter significantly enhances contrast and allows capturing faint nebulae, even in urban environments. Ideal for astrophotographers who want to achieve stunning results despite light pollution.