SLR Magic Variable ND Camera Lens Filter (52mm Rear Thread, 62mm Front)

The 0.4 to 1.8 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required. Once the front ring is rotated into a position that corresponds to the desired amount of density, the filter's rear ring can then be turned to lock the front ring into place, helping to ensure consistent exposures.

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