NiSi True Color Pro Nano Multi-Coated Brass Frame Circular Polarizer Filter 40.5mm

The NiSi True Color Pro Nano CPL (Brass Frame) is a professional circular polarizing filter built around NiSi's True Color polarizing material and a precision-milled brass frame finished in matte black. It eliminates non-metallic reflections, deepens skies, and lifts saturation in foliage and water, all while preserving the natural color balance of your scene, so images need less correction in post and stay true to what your eye saw on location.

Built for True Color
Many circular polarizers introduce a warm or yellow cast that shifts skin tones and skies. The True Color Pro Nano CPL uses NiSi's True Color polarizing material to deliver neutral, accurate color rendition, making it ideal for landscape, travel, portrait, and product photographers who rely on faithful color straight out of camera.

Cuts Reflections, Not QualityRotate the filter to tame glare from water, foliage, glass, painted surfaces, and wet rocks. Skies deepen, clouds gain contrast, and through-the-surface detail returns to lakes, rivers, and shop windows, all without sacrificing sharpness or introducing color shift.

Precision-Milled Brass Frame
The ultra-thin brass frame is precision-milled and finished in a clean matte black. Brass threads more smoothly than aluminum and is far less prone to binding on lens threads, even after years of use in the field, making installation and removal effortless.

Knurled Grip for Confident Handling
Knurled sides give your fingers something to bite into when the filter is cold, wet, or being used with gloves. Mounting and removing the CPL becomes quick and predictable, even in awkward shooting positions.

Removable Adjustment Knob
A small, knurled adjustment knob threads into the rotating ring to give you fast, fingertip control over polarization angle. When you prefer a streamlined profile, or need to stack additional filters, the knob unscrews and stows away in seconds.

Pro Nano Double-Sided Coating
Both surfaces of the optical glass are treated with NiSi's Pro Nano multi-layer anti-reflection coating. The coating suppresses flare and ghosting, repels water and oil, and resists fingerprints and dust, so the filter stays cleaner for longer and wipes down easily.

Optical Glass for High-Megapixel Sensors
Built with high-quality optical glass to preserve fine detail, the True Color Pro Nano CPL is engineered to keep up with today's highest-resolution full-frame and medium-format sensors without introducing softness or chromatic aberration.

A Size for Every Lens
Offered in thread sizes from 40.5mm through 105mm, the True Color Pro Nano CPL (Brass Frame) fits virtually every modern still and cine lens, from compact primes to large-diameter telephoto and wide-angle zooms.