The FotodioX 145mm Circular Polarizer Filteris compatible with the FotodioX WonderPana 145, FreeArc, and Absolute filter holder systems. It helps to reduce reflections as well as glare by filtering out light that has become polarized due to reflection from a non-metallic surface. The light from the sun naturally becomes partially polarized due to reflecting off electrons in air molecules, causing the light to scatter into what appears as haze. A polarizing filter arranges, and filters, this directionally polarized light perpendicularly to the reflected light, allowing for the absorption of much of this light. This results in a noticeable reduction of glare and reflections from non-metallic surfaces and an increase in the saturation of skies and foliage.

A circular polarizer only 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.

The FotodioX 145mm Circular Polarizer Filter is constructed from optical glass for clarity as well as color fidelity and features lightweight, aluminum-alloy filter rings. A rear filter ring connects to a compatible filter holder while four brass knobs along the side of the front filter ring allow the filter glass to be easily rotated. This provides the ability to achieve the desired degree of polarization even if another filter is placed in front of the FotodioX 145mm Circular Polarizer Filter.

Circular Polarizer Filter    For WonderPana 145, FreeArc, & Absolute    1.25 to 8x Filter Factor, +0.3 to 3 Stop    Helps to Eliminate Reflections and Glare    Reduces Haze in Landscapes    Greater Color and Tonal Saturation    Optical Glass Construction    145mm Front Filter Threads    Brass Filter Ring Rotation Knobs    Carrying Pouch

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° angle 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.

1.25 to 8x filter factor reduces exposure by 0.3 to 3 stops.

Constructed from optical glass for clarity.

Lightweight, aluminum-alloy filter rings along with four brass side knobs allow the filter glass to be easily rotated. The desired effect can be easily achieved even if another filter is placed directly in front.

Filter pouch included for storage and transport.

Related Questions and Answers

Q: 1. HiIs this a double or single threaded?Im trying to attach one more filter in front of it. Is that possible? Thanks

A: It is a single thread.

Q: 2. does this work on this system http://nikonrumors.com/2013/09/07/fotodiox-wonderpana-145-adapter-kit-for-the-nikon-14-24mm-f2-8-lens-review.aspx/and has anyone used it and liked the results??? susan

A: Yes, the FotodioX 145mm Pro Ultra Slim Neutral Density Filter is compatible with the Wonderpana 145 Adapter Kit for the Nikon 14-24mm f/2.8. Unfortunately, no one has reviewed this combination on our website.

Q: 3. Disregard its size, did anyone find this multi-coated UV filter degrade the image quality, such as sharpness?

A: When using the FotodioX 186mm Slim Multi-Coated UV Filter users have experienced no degradation of image quality, because the filter is made with optical glass and multicoated. The thin rim prevents vignetting, and the UV coating will help prevent glare from the sun.

Q: 4. Will this also fit the new f2.8 version of the 12-24?

A: No, this is for the f/4 version of the Sony 12-24mm zoom lens only.

Q: 5. does it work with the Rokinon 14mm 2.8 series II?

A: No, the FotodioX WonderPana 145 Core Unit for Rokinon/Samyang 14mm Lens with 145mm Circular Polarizer Filter only works with the Rokinon/Samyang 14mm f/2.8 ED AS IF UMC version one and the Rokinon 14mm T3.1 Cine lens.

Q: 6. How do you adjust the polarized lens to avoid the line through your picture? Without downloading pictures onto computer

A: Hi Jeff, you mean the black shade in a picture, if I take this between 12-16mm wide angle, right? It depends to the angle of the sunlight and in which angle I take that image. Usually it is not possible to adjust it in advance if you need to take that pic with 12mm wide angle.Bad luck...Best regards Vedat

Q: 7. how important is it for a cir polarizer filter to be multicoated?Will there be ghosting without multi coating?

A: Multi-coatings on a circular polarizer will greatly reduce the amount of ghosting and flare in a given image, however, a non-coated polarizer will not necessarily have ghosting.

Q: 8. Does the 5-stop (Ultra slim) filter allow stacking?

A: Yes, the Specifications state the FotodioX Pro 145mm Ultra Slim ND 1.5 Filter (5-Stop) has 145mm front filter threads which should allow you to connect an additional filter that has 145mm filter threads to the front of the filter.

Q: 9. what is filter thickness?

A: I REALLY DO NOT HAVE A DEMININSION IT IS THE SLIM FILTER THAT IS ALL I CAN TELL YOU.

Q: 10. Is this filter multi-coated? What is the difference between this filter and the Hoya 43mm NXT Circular Polarizer Filter (B&H # HOCPN43 MFR # A-NXT43CRPL)?

A: This polarizer is not multi-coated. The difference between this filter and the NXT filter is that Hoya NXT filters have over 97% average light transmission, and are constructed from heat-resistant, high-transparency optical glass.