The NiSi Explorer Collection 150x170mm Nano IR Medium Graduated Neutral Density Filter – GND8 (0.9) – 3 Stop is designed for adventure. These filters undergo a special glass hardening process that makes them twice as strong as typical glass filters. The Explorer series is much less prone to accidental breakage, making it perfect for active photographers.

This rectangular filter helps to darken specific areas of an image, such as bright skies, while allowing for a normal, unaffected exposure in other regions. The filter is densest at the edge and tapers to clear in the middle, featuring a medium-edged line of transition between the dense and clear areas. A neutral density filter with a medium-edged line of transition is particularly useful for images with buildings, small mountains, and other elements that extend high into the skyline. The transition zone of a medium is 40% smaller than a soft GND, making it ideal for shooting at sunrise and sunset.

NiSi GND filters do not affect the coloration of the image, offering true-to-life color. They are made from high-quality optical glass (not resin) with a nano coating to prevent loss of detail. Using a neutral density filter can make the camera vulnerable to infrared light, which may cast an unwanted red color in photos taken at a small aperture. NiSi GND filters have an infrared protection coating layer to eliminate infrared light through the lens, restoring natural true-to-life color.

The NiSi Explorer Collection is made from B270 tempered glass and features the same nano coating process as the optical glass filters. This filter is tempered and hardened, making it much less prone to accidental damage, although it is not unbreakable. Over time, the hardening may decline.