The Schneider 4.5" Mounted True-Pol 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. 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.

This filter is non-coated and delivers approximately 33% average light transmission. Constructed from Water White optical glass, this 4.5" filter is mounted for use in third-party or custom filter holders. No front or rear threads are included on this filter's ring or mount.

Mounted Circular Polarizer Filter    For Third-Party or Custom Holders    2.97x Filter Factor, +1.57 Stops    Helps to Eliminate Reflections and Glare    Reduces Haze in Landscapes    Greater Color and Tonal Saturation    Non-Coated    Water White Optical Glass    4.5" Filter Ring, Mount    Filter Pouch

Helps to reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface.

Mounted without front or rear threads for use in third-party or custom filter holders for film and television cameras.

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.

Non-coated.

Approximately 33% average light transmission.

2.97x filter factor reduces exposure by 1.57 stops.

Constructed from Water White optical glass.

Filter Pouch for storage and transport.

Related Questions and Answers

Q: 1. What does the Guide Plate do?

A: It's a guide is used for cutting filter gels - like ND, color etc - that slot into the back of the lens. Most likely not something that you will use very often.

Q: 2. What is the flange focusing distance at infinity? (Can I use it with tilt at a working distance of about 1 meter?)

A: According to Novoflex, you'll reach infinity with the PRO-PYRITE 90mm lens on the BALPRO bellows. Tilt and shift both depend on the camera. The smaller the camera plus adapter, the more movement is possible. For example, a Fuji GFX with the FUGPRO adapter or a Hasselblad-X camera with the HAXPRO will work very well, because the adapter and the flange focal length of these cameras are very small. On the other Hand, a Nikon D850 with the NIKA+APRO adapter will work, but the possible movement is limited, because the distance from the rear stand of the bellows to the sensor is much longer. And yes, it can be used at a one (1) meter range.

Q: 3. Will the Autofocus worked on my D3200?

A: The Sigma 8mm f/3.5 will not autofocus on a Nikon D3200.

Q: 4. Hi, can this product loop-through 1080p 50 video stream from hdmi input to sdi output? or it is only pass through by sdi i/oThanks

A: I'm afraid not. The SDI output is a loop-out from the SDI input only. It will not cross convert the HDMI input.

Q: 5. Can this lens be used and focused manually if used on older Nikon film bodies?

A: Yes, this could be used with any Nikon F-Mount body.

Q: 6. Would this case fit both the Sony 28mm-70mm kit lens and the Sony HVL-F20M flash. If not which Ruggard case size will be best?

A: You should be able to get both items in this case.

Q: 7. I see there is lots of padding, so are the dimensions listed the outside or inside dimensions?

A: The dimensions in the description are the maximum dimensions of the lens being held inside the case. The interior dimensions of the case are 4.5 x 4.8" while the exterior dimensions are 6.0 x 6.2".

Q: 8. What is the diameter of the image circle on this lens?

A: At the edges, which are slightly softened, the diameter would be about 21-22mm. The lens creates a black-bordered image on a FF sensor which is about 24mm high.

Q: 9. How many holders are in a package for $19.95? One or two or more? Do these holders work with Plustek 8200i SE?

A: It comes with 2 holders for 35mm mounted transparency (slide) film. They are compatible with Plustek 8200i SE.

Q: 10. will these work with 7500i?

A: I used to have a 7500i scanner but replaced it with an 8200i Ai scanner. So I do not know if the 8100 slide holder works on a 7500i scanner. It would have made sense if the holder dimensions would have been kept the same for both scanners. However, it may also be worthwhile to get the 8200i Ai scanner. It does a better job.