The NiSi 82mm Natural Night Filter blocks the yellow from sodium-vapor, mercury-vapor, and some LED lights common in urban areas that can make nightscapes less appealing. It will also enhance the visibility of astronomical objects by reducing the glare of nearby artificial sources of light. This filter will reduce your overall exposure by 1 stop. You may notice a slight pink or magenta cast to your results, which is normal and can be subdued in post according to personal preference. This is a great filter to have on hand whenever you're doing night sky shooting or evening cityscapes.