Tilta Khronos Magnetic FSND 2.1 Filter for iPhone - Black

The Tilta Khronos FSND 2.1 magnetic filter for iPhone cuts 7 stops of light, i.e. ND128. In bright light it keeps the cinematic 1/50 s shutter and smooth motion; for stills it extends the exposure 128×. It drops magnetically into the Khronos quick release filter tray on a Khronos case for iPhone 15, 16 and 17 Pro / Pro Max. Black frame.

Tilta Khronos Magnetic FSND 2.1 is a neutral density filter for iPhone within the Khronos system. In strong light the phone copes by shortening the shutter, and the video stutters — an ND filter takes the light away so the shutter can stay cinematic. This one has optical density 2.1: 7 stops, designation ND128.

Into the Khronos filter tray

The filter is a single glass covering all three iPhone lenses. It drops into the Khronos quick release filter tray, where a magnet holds it — fitting or swapping takes a second, no threads, even mid-shoot. The tray attaches magnetically to the Khronos case and swings down over the lenses. The glass is far thinner and lighter than conventional screw-in filters. Tray and case are not included — without them the filter has nothing to hold on to.

FSND 2.1: 7 stops, ND128

Optical density 2.1 cuts 7 stops of light and extends the exposure 128×. On a bright day that keeps the shutter at 1/50 s with natural motion blur; for stills it lengthens the time. Full Spectrum ND attenuates the whole spectrum evenly — visible light, UV and infrared — so colours stay true with no cast. The multi-layer anti-reflective coating limits reflections and flares, and the glass also protects the lenses from scratches, smudges and debris.

Versions

The filter frame is black; the same glass also comes with a Space Gray frame (TK-IP-ND21). The FSND range has eight densities from 0.3 (1 stop) to 2.4 (8 stops), all the same thickness, so they swap in the tray without changing focus or framing. The tray takes one filter at a time.

The Tilta Khronos ecosystem

Khronos is a modular system for shooting with a phone: a case or cage with mounting points that take magnetic filters, cooling, handles, lights, a USB-C hub and brackets via quick release. The parts combine and carry over between phone generations — this one is among them.