At around $90 for a wide 1-9 stop variable ND, the K&F Concept Nano-X Variable ND ND2-400 is the value pick. Digital Camera World scored it 4/5, praising the 28-layer nanocoating and handling while noting it softens detail slightly. Photography Life and Digital Photography School both found the color cast minor and easily corrected.
- — Wide ND2-ND400 (1-9 stop) range in one filter
- — Putter-style adjustment handle with stops marked on the frame
- — 28-layer nanocoating that is water- and oil-repellent
- — Slight softening of detail and minor warm color shift
- — X-pattern cross-polarization at the highest settings