ENHANCED CONTRAST - This Baader Planetarium Ca-K filter isolates the 394nm wavelength, revealing high-contrast details on the Sun's surface for stunning solar photography. SUPERIOR FILTER QUALITY - Crafted with dielectrically coated, planeoptically polished glass, this narrowband filter ensures exceptional image clarity and minimal light scatter. PRECISE WAVELENGTH CONTROL - Featuring a 5nm HBW (Half Bandwidth) and 394nm CWL (Central Wavelength), this filter delivers accurate and consistent solar details every time. OPTIMIZED LIGHT TRANSMISSION - Designed for photographic use behind another solar filter, it allows precise light transmission, crucial for capturing detailed solar images safely.