The Sigma 105mm DG Single-Layer Coated Circular Polarizer Filter helps to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface. This results in a noticeable increase in the saturation of skies and foliage, as well as clearer imagery when photographing in hazy conditions.
A circular polarizer differs from a linear polarizer in that it contains a quarter wave plane in addition to the linear polarizing filter. The addition of this quarter wave plane is to circularly polarize the linearly polarized light for the use of auto focus and exposure functions. Due to how the light is broken down and filtered with a linear polarizer, auto focus and exposure accuracy become skewed during use. When the light becomes circularly polarized, it permits the use of these functions.
This filter features a single-layer coating to help reduce surface reflection and ghosting while helping to increase overall clarity and contrast.
Helps to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface.
Polarizing filters arrange, and filter, directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of the light.
Clears up haze in distant landscapes and provides more saturated, vivid colors.
Strongest effect when used at a 90° from the sun.
Circular polarizers are ideal for use with digital cameras and autofocus lenses where a linear polarizer will often disrupt auto exposure and focus features.
Single-layer coating provides a reduction in surface reflections and helps to reduce flare and ghosting.
About 2.5 (1.3 stops)
Eliminates reflections and haze and improves color and tonal saturation