The Heliopan Bay 70 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.

The filter ring is constructed out of matte black brass, which provides durability and further prevention from glare. They also feature high quality Schott glass for greater optical clarity and color fidelity. The Bay 70 mount is compatible with the Hasselblad-specific bayonet lens mount.

Helps to Eliminate Reflections and Glare    Reduces Haze and Blue Cast in Landscapes    Greater Color and Tonal Saturation    Brass Ring Construction for Durability    High Quality Schott Glass

Helps to reduce reflections and glare by filtering out light that has become polarized due to reflection off of 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.

Durable brass ring construction and Schott glass for optical clarity.

Related Questions and Answers

Q: 1. Is this lens compatible with the Rebel T3i?

A: The EF 70-300mm f/4-5.6 IS USM lens is compatible with the Canon T3I.

Q: 2. What is the range on a small sensor camera like the 7d?

A: To find the full-frame equivalent focal length of any lens used on a Canon APS-C sensor camera, you simply multiply the focal length of the lens by 1.6x. As such, 70-300mm x 1.6 = 112-480mm. The lens would have an full frame equivalent focal length of a 112-480mm lens.

Q: 3. If this lens is used with a Canon 12 mm extension tube, what would the close-focusing distance be? Using the 12 mm Canon extension tube, would you still have auto focus and other functionality?

A: When using a Canon 12mm Extension Tube with this lens, the focusing distance would be shortened by 12mm.

Q: 4. Will this lens work with aps-c sensor cameras?

A: Yes, this lens works with the APS-C cameras. I have the 70D and it is a good lens.

Q: 5. Anyone seeing dust accumulation inside the lens yet?

A: We have had no reports of dust accumulation inside this lens.

Q: 6. Is the Canon EF 70-300 f4-5.6 compatible with the Canon 70d?

A: Dear Norman,The Canon 70-300L IS works perfectly with the Canon 70D. I used that very combination on a safari to Tanzania in March 2014 and have used it extensively since then. I hope that answers your question.

Q: 7. Is this lens sharp wide open?

A: Hello, I bought this lens and experienced it. This is a good lens and you can get sharp video and pictures. However, the lens should be on tripod cause it does not have image stabilization. The price is great. Hope I answered your question. charlie

Q: 8. I see that in the box does not include a bag that typically comes with a Canon lens. No bag?

A: That's correct. Canon on many non-professional lenses does not always supply accessories such as a bag or case or hood. Unfortunately for this model they opt to distribute it without these items in order to keep the cost down. We do feature several options under the Accessories tab on this link to choose from.

Q: 9. Is this compatible with Canon 80D?

A: Yes, it is fully compatible with the 80D.

Q: 10. Is a lens hood included? I don't see it mentioned anywhere.

A: Yes, a lens hood is included.