One of the most important obstacles for the exploration of the night sky is the brightening of the night sky by artificial lights, such as streetlights. The night sky is not really dark in the vicinity of towns or cities, which reduces the visibility of objects beyond the solar systems enormously. The Explore Scientific CLS nebula filter blocks those colors and thereby increases contrast - the light ot the celestial objects can pass the filter. The result is astonishing: suddenly objects are visible at locations that were completely empty without filters. In suburban skies for example the large galaxy M101, the Veil-nebula Ngc 6992 or even the bright Dumbbell-nebula M27 are not clearly visible. By using this filter you can see the nebulae and their structures. The Explore Scientific nebula filters come with a individual test certificate - your guarantee to receive a premium filter. Explore Scientific 2" CLS City Light Pollution Reduction Filter. Range from 436nm to 536nm with peak at 488nm. Peak transmission 98.3%
