This Kase 90mm Magnetic Circular Polarizer Filter is compatible with a Kase K9 100mm Filter Holder. It helps to reduce reflections and 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.

Mounted within a non-threaded, steel filter ring, this filter is made specifically to fit within a separately available Kase 90mm Magnetic Lens Adapter Ring behind a Kase K9 100mm Filter Holder. Constructed from Schott B270 Superwhite glass for enhanced clarity and color fidelity, each glass surface includes multiple layers of anti-reflection coatings to prevent internal ghosting and reflections. These coatings also offer greater protection to the filter substrate and help it to stay clean for longer than with uncoated filters.

For Kase K9 100mm Filter Holder    Magnetic, Drop-in Circular Polarizer    2x Filter Factor, +1 Stop    Helps to Eliminate Reflections and Glare    Reduces Haze in Landscapes    Schott B270 Superwhite Glass    Multi-Coated Surfaces    Scratch and Mold Resistant, Hydrophobic    Plastic Case

• Drop-in magnetic circular polarizer filter for separately available Kase K9 100mm Filter Holder
• Polarizer filters help to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface, clear up haze in distant landscapes, and provide more saturated, vivid colors
• Does not disrupt auto exposure or focus features and is constructed from Schott B270 Superwhite glass for enhanced clarity and color fidelity
• Multi-coated to prevent internal ghosting and reflections and features scratch-resistant, mold-resistant, and hydrophobic coatings on each glass surface to protect the filter substrate and result in an improved beading effect when in contact with water or oil for greater cleaning efficiency
• 2x filter factor reduces exposure by 1 stop
• Designed to avoid vignetting when used with a wide-angle lens and can be independently rotated to adjust the intensity of the polarization effect
• Plastic case for storage and transport

Related Questions and Answers

Q: 1. Will this work with a 95mm filter thread? The Canon RF 28-70 specifically.

A: No, the Kase K9 100mm Filter Holder Kit does not have a 95mm adapter to work with the Canon RF 28-70mm f/2 L USM Lens. For that lens you would need the Kase Armour Holder.

Q: 2. Does "Kase K9 Adapter for Nikon Z 14-24mm f/2.8 S Lens, B&H #KA1111080052" make this kit compatible with the Nikon 14-24 Z?

A: Yes, the Kase K9 Adapter for Nikon NIKKOR Z 14-24mm f/2.8 S Lens will allow you to connect the Kase K9 100mm Slim High-End Filter Holder Kit to the Nikon NIKKOR Z 14-24mm f/2.8 S Lens.

Q: 3. Could I use an older Lee hood that clips onto the front slot with this holder?

A: I'm sorry the Lee hood is not compatible.

Q: 4. Does this filter allow full movement of a Laowa 15mm shift lens?

A: The Kase K9 100mm Filter Holder with the Kase 90mm Magnetic Circular Polarizer Filter for Kase K9 100mm Filter Holder will not fit on the Venus Optics Laowa 15mm f/4.5 Zero-D Shift Lens.

Q: 5. Which Kase CPL will work with the K9 100mm Filter Holder for the Nikon Z 14-24mm lens?

A: Unfortunately, it is not possible to use the round Kase 90mm Magnetic Circular Polarizer Filter for Kase K9 100mm Filter Holder with the Kase K9 100mm Filter Holder Kit for Nikon Z 14-24mm f/2.8 S Lens. As an alternative, I would instead recommend purchasing the Kase 100 x 100mm Skyeye CPL Filter, B&H # KASECPL44 • MFR # K-100-CPL, for your usage needs.

Q: 6. Will Kase 9 cause vignetting on Nikon 14-30 at 14mm ?

A: As per the manufacturer, it is suggested to directly attach the holder’s geared adapter rings onto the lens thread where possible to prevent vignetting. However, this holder has not been tested on a Nikon Z 14-30mm f/4 lens specifically to our knowledge. Your results may vary.

Q: 7. What is the country of origin for this filter and filter holder?

A: The country of origin of the Kase K9 100mm Filter Holder Kit is China. However, the country of origin is subject to change.

Q: 8. Will this "Kase K9 100mm Filter Holder Kit" with either the included 90mm CPL filter or a 100x100mm filter cause vignetting for either a Sony 24mm f1.4 FE GM lens or a Sony 35mm f1.4 FE GM lens?

A: Neither of your wide-angle lenses will get vignetting mounted on a Sony full-frame camera with Kase K9 100mm Filter Holder Kit because the lens adapter expands on top of your lens to 90mm. Yes the Kase 90mm Magnetic Circular Polarizer Filter for Kase K9 100mm Filter Holder is included in the kit.

Q: 9. Will the Kase K9 filter holder work with the Nikon 14-24 f2.8 S (Native Z mount) lens? If so,what size filter adapter is required for the rectangular filters.

A: No, unfortunately, Nikon NIKKOR Z 14-24mm f/2.8 S Lens won't work with Kase K9 100mm Filter Holder Kit. The only way to attach an adapter ring to the lens is using the lens hood which has a built-in thread of 112mm. The largest adapter ring for Kase K9 is only 82mm.

Q: 10. will this work on an Olympus 7-14mm lens?

A: The Kase K9 100mm Filter Holder Kit can be used on the Olympus M.Zuiko Digital ED 7-14mm f/2.8 PRO Lens with the use the proper adapter. One can use the Kase K9 Adapter for Olympus M.Zuiko 7-14mm f/2.8 PRO Lens, BH #KAO714AK9 (https://bhpho.to/3AUL6CE).