Chroma LoGlow Light Pollution Filter The Chroma LoGlow Light Pollution Filter blocks common spectral lines from lighting sources. This filter provides balanced color for the visible spectrum while blocking most emission from metal-halide and vapor lamp sources which together contribute to sky glow. Chroma Technology is an employee-owned company. They specialize in the design and manufacture of sputtered optical filters and coatings for applications that require the greatest precision in color separation, optical quality and signal purity. Their astronomical filters are used worldwide in research and amateur applications. They are as comfortable designing and manufacturing custom filters as they are for their catalog items. Highly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f/4 or smaller. Chroma provides custom coating services for more demanding imaging applications requiring larger apertures such as f/3 or f/2. They also can provide larger sizes and unique passbands upon request. Chroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission. All filters are manufactured in Vermont. Additional Features: Blocks common spectral lines from lighting sources. This filter provides balanced color for the visible spectrum while blocking most emission from metal-halide and vapor lamp sources which together contribute to sky glow. Extremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accuratein CWL and band pass adherence No reflections leading to image distortions or “back reflections” Technical Specifications T: ≥ 94% avg. across visible passbandsBlocking ≥ OD1.4@ metal-halide and vapor lamp linesDurable sputter coatingsParallelism:
