The moon and the stars no longer come to the farm. The
farmer has exchanged his birthright in them for the wattage of his
all-night sun. His children will never know the blessed dark of night.
— Leslie Peltier in his autobiography
Golden Bridge, Los Angeles – Before and After
Even in one of the brightest cities on Earth, the hidden beauty of the night sky can still be revealed. This composite image of the Golden Bridge in Los Angeles shows two worlds in one frame — the left half captures the harsh glow of urban light pollution, while the right half reveals what the same scene looks like after careful digital correction.
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| Light pollution Astrophotography Urban Astronomy |
The difference is striking. On the left, the orange sky glow typical of large cities drowns out all but the brightest stars. On the right, subtle gradient removal and color correction bring back the natural depth of the night sky. No Milky Way is visible here — just the quiet, real sky above Los Angeles as it would appear without the interference of artificial light.
Photoshop Processing Steps for Light Pollution Removal
The following steps describe exactly how I processed the Golden Bridge image to reduce light pollution and restore the natural night sky appearance. This simple method can be repeated for other urban nightscapes.
Step1: Select the Layers panel and then duplicate the layer
Step 2: Filter -> Noise -> Median… (about 50 px)Step 3: Filter-> Blue -> Gaussian Blue… (about 30px)
Step 4: Select original layer
Step 5: Image -> Apply image (Blending: Subtract; Offset: 40)
Step 6: Delete the duplicate layer
In this photo, the digital cleanup was done using gradient-removal layers in Photoshop and subtle color balance adjustments. The goal wasn’t to create an unrealistic night sky, but to recover the true dynamic range that excessive lighting had hidden. The restored image shows a faint trace of the starry night rising over the bridge — a reminder that the night is never completely lost to light.
See also for example video in my other post: Comet 103P/Hartley 2 from New York City
Note, that Astronomy Tools has more sophisticated methods to remove light pollution, or you can do some variations of such methods (it depends from size of you original image). You also can apply it only for part of original image.
The other way to remove light pollution is using multiple images, see for example my other post: M42 Orion Nebula using iOptron SkyTracker in NYC
Why Light Pollution Happens
Light pollution occurs when artificial lights scatter in the atmosphere and overpower natural celestial light. Sodium and LED streetlights create broad orange or blue glows that spread for tens of kilometers, reducing contrast in photos and drowning out faint stars. For astrophotographers, it’s the biggest obstacle between the camera and the universe.
Preserving the Night Sky
As urban areas expand, the number of places with truly dark skies continues to shrink. Each successful image that recovers the stars from behind the glow is not just an artistic act — it’s also a message about preservation. Protecting our night environment helps both wildlife and human curiosity. After all, the sky is our oldest map of time.
Final Thoughts
Removing light pollution is part art, part science, and part patience. Whether working from a city balcony or a remote desert, every photographer can uncover the universe hidden behind the glow. The Golden Bridge image proves that even in the heart of Los Angeles, the stars are still there — waiting to be revealed.
Related Astrophotography Posts
- M42 Orion Nebula using iOptron SkyTracker in NYC
- Comet 103P/Hartley 2 from New York City
- The Solar Eclipse of April 8, 2024: An HDR Revelation of the Sun's Corona from Westport, New York
- Why the Equatorial Sky Glows More Red - My Nights Photographing Airglow in Tanzania and the Galápagos
- Topaz DeNoise AI Canon Ra Milky Way Astrophotography
