LoGlow Light Pollution Filter: How It Works

Quick answer

The LoGlow Light Pollution Filter is a broadband filter that blocks specific wavelengths from metal-halide and vapor lamps, restoring natural color to your views and images under light-polluted skies.

Diagnosis: Is the LoGlow filter right for your situation?

• Symptom: Your night sky has a bright orange or yellow glow that washes out faint objects, especially from a suburban or city location.
• Likely cause: The glow is from nearby streetlights or building lights that use metal-halide or high-pressure sodium vapor lamps. These emit strong, narrow spectral lines that scatter in the atmosphere. Check the type of lighting in your area. If most lights are LED (broad spectrum), a broadband filter will be less effective.
• Corrective action: Attach the LoGlow Light Pollution Filter to your telescope's eyepiece or camera nosepiece. The filter blocks the offending spectral lines while passing the rest of the visible spectrum, darkening the sky background and improving contrast on nebulae, galaxies, and star clusters. Try a single session with the filter on a bright nebula like M42 or M57. If contrast improves noticeably, it's working for your site.
• Stop or choose another option: If your primary target is faint emission nebulae and you already have a narrowband filter set, the LoGlow may not add enough contrast. Consider a dedicated narrowband filter for those objects. Also, if most local lights are white LEDs, a broadband filter will have limited effect. For LED-heavy areas, look into a multi-band or dual-band filter designed for modern lighting.

Product facts

• LoGlow Light Pollution Filter: Blocks common spectral lines from metal-halide and vapor lamp sources that contribute to sky glow. This means the filter targets the exact wavelengths that cause urban light pollution, so you get a darker background without muting the rest of the spectrum.