NiSi 100mm Natural Night Filter: Cut Light Pollution Glow

By NiSi Filters Australia | Published: 2026-11-01

Category: How-to Guides

Learn a repeatable workflow for the NiSi 100x100mm Natural Night Filter to tame orange sky glow in long exposures and cityscapes, from setup to final tweaks.

Quick answer

Mount the NiSi 100x100mm Natural Night Filter in your 100mm holder, set a long exposure with a low ISO, and fine-tune white balance in post to cut orange sky glow while keeping stars and city detail clean.

Why the filter helps and when it does not

The NiSi Natural Night Filter targets the sodium-vapor wavelengths that create orange sky glow in urban night scenes. It works best when that glow is the dominant light source; under mixed LED and tungsten lighting, the effect is subtler and may require a different white balance approach.

For astrophotography, the filter can improve contrast between stars and skyglow, but it will not replace dark skies. Expect cleaner cityscapes and suburban nightscapes rather than deep-sky performance.

Exposure and white balance starting points

Start with ISO 100–400 and an aperture of f/8–f/11 for cityscapes, then extend shutter speed until the histogram sits left of center without clipping highlights. For star fields, open to f/2.8–f/4 and use the 500 rule as a rough shutter limit to avoid trailing.

Set white balance to Daylight or around 4000K as a neutral baseline, then adjust in post. Avoid Auto White Balance, which can shift between frames and complicate blending.

Step-by-step: using the NiSi 100mm Natural Night Filter

Mount the filter in your 100mm holder: Slide the 100x100mm filter into the holder slots, ensuring it sits flat and fully seated. Common mistake: inserting it at an angle, which causes vignetting and light leaks. Check that the filter is flush and the holder is locked before shooting.
Set a manual exposure baseline: Switch to manual mode, set ISO 100–400, choose f/8–f/11 for cityscapes or f/2.8–f/4 for stars, and use a shutter speed that keeps the histogram left of center. Common mistake: relying on auto exposure, which can overexpose highlights. Take one test frame and review the histogram before committing to a long exposure.
Lock white balance and focus: Set white balance to Daylight (~5500K) or 4000K, then focus manually at infinity or on a distant light, and switch to manual focus. Common mistake: leaving autofocus on, which hunts in low light. Use live view magnification to confirm critical focus.
Shoot a test exposure and adjust: Take a 10–30 second test shot, review for glow reduction and star sharpness, then adjust shutter speed or ISO as needed. Common mistake: judging results on the camera LCD without checking the histogram. If orange glow persists, try a slightly longer exposure rather than raising ISO.
Refine in post-processing: Import RAW files, adjust white balance toward cooler tones, and use local adjustments to reduce residual glow. Common mistake: overcorrecting white balance, which turns skies unnaturally blue. Compare before-and-after versions to keep the night mood intact.

Product facts

NiSi 100x100mm Natural Night Filter (Light Pollution Filter): NANO Coating technology for minimal ghosting and flare. This matters for night scenes with bright light sources, where internal reflections can otherwise ruin contrast.
NiSi 100x100mm Natural Night Filter (Light Pollution Filter)