LockCircle Prime Circle 4×5.65 1.8 (6 stops) ND Filter
The PrimeCircle 4×5.65 1.8 ND filter from LockCircle, produce a grey neutral tone and are used to reduce light, enabling more control over exposure and depth of field without affecting color or contrast. ND Glass filters are especially useful in bright light conditions to avoid overexposure. When using wider lenses they adjust exposure correctly, allowing for reduced depth of field. This enables highlighting of the principal subject and taking the foreground or background out of focus.
PrimeCircle filters are diamond cut from German Ultra-White optical glass, the best quality solution for modern high resolution lenses! The parallel relationship between front and rear surfaces (important for the best optical performance) is verified with a laser interferometer and a densitometer is used for testing consistent density. To check proper light transmission is also used a spectrophotometer!