This 67mm lg counter depth refrigerator water filteris an ND filter with a 8x filter factor that provides a 3-stop exposure reduction. Its 0.9 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required. By increasing your aperture or slowing your exposure time, you are able to control depth of field and convey movement more easily. Neutral density filters are intended to not affect the coloration of the image and are ideal for pairing with other filters.

The design of this filter has been optimized for use with digital sensors and to promote nearly flat attenuation of visible light and infrared light. Due to imaging sensors' greater susceptibility to infrared light, compared to traditional film, color casts can occur when photographing darker subjects that require increased exposure times.

This filter is constructed from Water White glass for increased clarity as well as color fidelity. It is made using ColorCore technology, a process that involves laminating the filter substrate between two pieces of optical glass, grinding flat to a tolerance of 1/10,000th of an inch, and then mounting to precision metal rings.

0.9 Optical Density    Water White Glass Construction    ColorCore Technology    67mm Front Filter Threads    Darkens Entire Image    Allows Reduced Shutter Speed    Allows Wider Aperture    Neutral Results, Visible & IR Spectrums    Includes Plastic Case

0.9 neutral density filter darkens the image, allowing you to photograph with a longer shutter speed or wider aperture than normally required.

Providing a 3-stop exposure reduction, this filter allows you to control depth of field and convey movement more easily.

Attenuates infrared light to maintain color neutrality and suppress color casts due to increased exposure lengths.

Filter does not affect coloration of the image and is ideal for use with other filters.

Constructed from Water White glass for increased optical clarity.

67mm front filter threads allow for use with other filters.

Plastic filter case for storage and transport.

Related Questions and Answers

Q: 1. can someone please tell me how to assemble the impact 10 pound counterweight?

A: no assembly required and the weight works rather well as counter balance

Q: 2. what is the difference between sigma WR protector clear glass filter 95mm vs Sigma WR Ceramic protector filter 95mm ?

A: The WR Ceramic Protector Filter would use a clear glass ceramic substrate which has added strength and a higher transmittance value over the WR Protector Filter which uses a glass element that is not as strong.

Q: 3. Please confirm whether separate purchase of the 01147-011 people counter license is required or if it's included?

A: A license is not required when using the AXIS P8815-2 3D People Counter.

Q: 4. i just opened the box and it needs to be assembled and I didn't receive instructions....can someone tell me how?

A: There are no instructions on the counterweight. But this is a drawing for a different version but is similar and it shows it broken down, http://bit.ly/1FnABb5.

Q: 5. What is the light transmission of this?

A: Sigma does not have any published specifications for light transmission of this CPL (which I believe is typical because most CPLs have filter factors in a range) but does advertise a 30% increased transmission over their competitors' CPLs. This filter does have a 0.3-0.5 stop reduction of light, which equates to a theoretical numerical transmission of 81.2% (at 0.3 stops) to 70.7% (at 0.5 stops), the formula being 100% multiplied by half to the power of 0.3 and 0.5.

Q: 6. Is there any quality degradation on 150-600mm lens, at focal lenghts beyond 200mm?

A: The Sigma 95mm WR (Water Repellent) Circular Polarizer Filter would have the same effect on the lens at all focal lengths. While adding any optic in front of the optical formula of your lens will have some amount of effect to your lens' image quality, the Sigma 95mm WR (Water Repellent) Circular Polarizer Filter is a high-quality filter, and the benefit of its circular polarizing performance in reducing glare/flare from non-metallic items, increasing contrast/saturation, and deepening the blue hue in the sky (depending on your orientation to the sun) would mitigate any minor negative degradation you would obtain from using the filter on your lens.

Q: 7. Any vignetting when mounted on a Zeiss 15mm lenses on Nikon D810?

A: This filter may cause vignette when mounted on a full frame camera and 15mm lens.

Q: 8. why am I having problems with scratches on the glasswhy am i getting scratches on the glass?

A: A filter like a lens is still glass and is sensitive to scratches like any other lens.Some filters are better than others. But a lens cap still needs to be used when using filter to protect it when you put it in a camera bag.

Q: 9. The plate tightens down, but there's no way it would tighten enough to be secured to a grip arm. Are you supposed to remove the HEX screws and move the plate to the lower section, using only two screws?

A: Loosen the hex and the main screw fully. Place the weight on the arm, then tighten the hex screws so that the plate is snug - this will move the plate down. Then fully tighten with the main screw clamp. The hex screws are there to allow travel of the plate for different sized (diameter) arms...

Q: 10. Is this binder suitable for archival storage of photos that are themselves in archival sleeves?

A: The binder itself is not archival and depending on how the binder with photos in pages is stored (heat, humidity and such) it may overtime release some gases harmful to your photos.