NiSi Square Nano IRGND Reverse 100x150mm GND16 1.2

NiSi Square Nano IR GND Reverse 100x150mm – Reverse Graduated ND for Sunrise and Sunset Horizon Control

The NiSi Reverse Nano IR Graduated Neutral Density (GND) filter is built for landscape photographers who work with strong horizon light, especially during sunrises and sunsets. It uses a reverse graduation that places the darkest area near the horizon, then fades to clear toward the top, helping you control bright skyline highlights without affecting the foreground exposure.

Key benefits and intended use

This reverse GND design manages the intense light that often concentrates at the horizon line during sunrise and sunset. You can reposition the filter in a holder to recompose the scene and align the transition precisely with the skyline. As a neutral density filter, it does not change the coloration of your image.

Materials and coatings

• Made from high quality optical glass (not resin).
• Environmental Optical Lens glass (H-K9L) construction.
• Nano coating on both sides to protect image detail and provide water and oil repellency.
• Infrared (IR) protection coating to reduce unwanted red cast caused by infrared light when shooting at small apertures.

Optical characteristics and performance

Neutral density filtration in this product is applied with a reverse hard edge: the darkest area sits near the middle/horizon and becomes gradually clearer toward the top of the filter. This layout allows you to protect the skyline from overexposure while keeping the lower portion clear. The filter is designed to maintain high definition output, with ultra low color cast and ultra low reflection, and it is specified to produce no vignetting when used correctly.

Available strengths

The NiSi Reverse Nano IR GND for 100x150 mm holders is available in the following maximum-effect aperture steps:

• 3 stop (0.9)
• 4 stop (1.2)

How to use

Insert the filter into a compatible 100x150 mm holder and slide it up or down to position the dark band at the horizon or bright line in your composition. Because the filter can be repositioned within the holder, you can recompose the frame after placing the filter to achieve the desired balance between sky and foreground exposure.

Technical specifications

Smart FAQ

Question: How does a reverse GND differ from a standard graduated ND and when should I use it?
Answer: A reverse GND places the darkest area at the horizon and fades toward the top, unlike a standard GND that darkens from the top down. Use it for sunrise and sunset scenes where the brightest light concentrates at the horizon line, so you can control skyline highlights without darkening the upper sky excessively.

Question: Will this filter change the colors in my photos?
Answer: No. Neutral density filters do not affect coloration. In addition, this NiSi filter features ultra low color cast and an IR protection coating to help preserve natural colors and reduce infrared-induced red casts at small apertures.

Question: Is this filter glass or resin, and how does that affect image quality?
Answer: This filter is made from high quality optical glass (not resin). Glass construction combined with nano coatings helps maintain high definition and protect fine detail in your images.

Question: Which strengths are available and how do I choose one?
Answer: The filter is available in 3 stop (0.9) and 4 stop (1.2) strengths. Choose the strength based on how much you need to reduce the brightness of the horizon relative to the rest of the scene; stronger stops provide greater reduction for very bright horizons.

Question: Will this filter cause vignetting or reflection issues?
Answer: The filter is specified to have ultra low reflection and no vignetting when used appropriately in a compatible 100x150 mm holder. Proper positioning and the correct holder setup will help avoid unwanted edge darkening or reflections.