138mm Letterbox Diopter Strength:2 1 density gives a subtle

1 density gives a subtle fog effect

Compact vests are designed for thinner

reduces ISO by 1/4) ND

Filters help to reduce dust and moisture from reaching your lens element and provide additional protection in case of drops or situations where scratching could occur

Maintains greater sharpness and is less affected by highlight-flare than the standard Fog filter

138mm Letterbox Diopter Strength:2 1 density gives a subtleLetter Box Diopters are considered the reverse of the Strip Diopters. An open slot in the center (similar to a slot in a mail letter box) is flanked by diopter glass on either side. These diopters allow you to create interesting effects while experimenting and allow you to achieve varied focus, diffusion and double imaging effects. They come in 15mm and 30mm formats.