This Kase Filter Kit for Canon EF 300mm f/2.8L IS USM Lensincludes a UV filter and a circular polarizer filter. Each filter in this kit can provide one of two enhancements to your imagery while using a Canon EF 300mm f/2.8L IS USM Lens. A UV filter adapter ring is also provided, as well as a lens cap, and a filter case that can accommodate both filters, which feature multi-coated Schott B270 Superwhite glass for enhanced clarity and color fidelity.

A general-use, clear filter designed to absorb ultraviolet light and reduce the bluish cast of daylight, the UV Filter can be screwed on after the UV filter adapter ring is installed along the front of a compatible lens. Aside from the reduction of unwanted blue casts, no additional coloration or contrast is created while using this filter, and adjustments to exposure are not required. The UV filter is also useful as a general protective filter to leave on a Canon EF 300mm f/2.8L IS USM Lens at all times. Such filters help to reduce dust and moisture from reaching the front lens element and provide additional protection in case of situations where scratching could occur.

The 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. It is made specifically to fit within the accessory filter slot of the Canon EF 300mm f/2.8L IS USM Lens. With that lens, the effect of this filter occurs behind the main glass elements instead of in front of them.

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.

The circular polarizer filter includes an integrated locking mechanism to secure it within the compatible lens, as well as an external dial to allow rotation of the filter glass for control of the polarization effect.

Screw-On UV Filter with Adapter Ring    Absorbs Ultraviolet Light    Reduces Bluish Cast of Daylight    1x Filter Factor, No Exposure Change    Drop-In Circular Polarizer Filter    2 Filter Factor, +1 Stop    Helps to Eliminate Reflections and Glare    Reduces Haze in Landscapes    Greater Color and Tonal Saturation    Lens Cap, Storage Pouch

• Absorbs UV light and reduces bluish cast of daylight
• Does not require adjustments to exposure while in use
• Creates no additional coloration or contrast
• General protection filter reduces dust, moisture, and scratches from reaching lens elements
• Schott B270 Superwhite glass for enhanced clarity and color fidelity
• Multi-coated to prevent internal ghosting and reflections

• 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
• 2x filter factor reduces exposure by 1 stop
• Schott B270 Superwhite glass for enhanced clarity and color fidelity
• Multi-coated to prevent internal ghosting and reflections

Related Questions and Answers

Q: 1. Can you auto focus with the 2.0xiii extender ?

A: Yes and no - just tried it a few weeks ago. It worked, but extremely slowly and sometimes didn't focus on what I'd want, so I find manual focusing with the 2x is easier. By itself though, the 300 4.0L is fast at focusing.

Q: 2. can the lens hood be Reattached in shooting position once this UV filter is attached?

A: Yes, the lens hood can be reattached once you install the Kase UV filter on the lens.

Q: 3. How much does the detachable tripod collar weigh?

A: 4.1 oz or 117 gram

Q: 4. I am interested in getting this lens for use on a Sony A7-II, as there is no E-mount equivalent. Does anyone have experience using this with a Metabones or Sigma MC-11 adapter? Does autofocus work with either of those on a Sony?

A: When using a 3rd party lens adapter and used to mate the lens and camera from two different companies, the issue always is the speed of the AF performance. As of now, even the very best is behind OEM performance. That being said, the best Metabones adapter with this lens should prove very satisfactory. While Sigma will not support the use of the MC-11 with other manufacturer lenses, many users have reported success with the MC-11 with non-Sigma lenses while an equal number have reported failure. Generally, the latest model lenses seem to work. We could find no reports of the MC-11 and this older design lens unfortunately.

Q: 5. Is the tripod mount supplied with the lens

A: Yes, the tripod mount ring is included with the Canon EF 300mm f/4L lens.

Q: 6. Will the 300mm f/4 IS work with a EF 2x extender 111 on a T3i ?

A: It works with a 1.4x III on my T1i but with noticeable loss of resolution, so expect worse with 2.0X. Autofocus should still work as it would only go to f/8 effective.Bear in mind it only has the first-generation stabilizer two-stops at best.I bit the bullet and got the 100-400 f/4.5-5.6 L IS II. I get outstanding results with a 1.4x III (560mm effective) on that.I still use the 300mm f/4 as is for hiking on hard trails as it is so much lighter.

Q: 7. i want to know how it compares to the Sigma dg 500mm lens i have, is it the same sharpness if so i will stick with my 500 sigma?

A: in all fairness I really can only remark on the canon 300 f4 lens as I do not own the Sigma 500, to be honest it would be hard to compare the two as both are different focal lengths so its an apple to oranges comparison in that respect ,however as far as the 300 f4 canon goes I am totally happy with its performance as far as sharpness ,image stabilization (as others have mentioned its a litttle noisy & its an older version of IS ) easily hand hold hold able . I have used it to photograph small birds and have occasionally used it for weddings where my 70-200 2.8 is lens is not long enough .

Q: 8. Hi How good is this compared to the canon 70-300 L IQ,IS?Thanks

A: I am not familiar with the lens in your question. I use the 300 f4 for wildlife and sports, but use the 70-200 f 2.8 and the 200-400 f4.5/5.6 for most of My sports work. The 300 fixed lens is excellent for shooting consistant distances where most of the action takes place, and works well with a 2x extender.

Q: 9. Does the 300mm f/4.0 IS USM lens work with an extender 1.4x II on a 60D camera body?

A: Yes, the 300 mm f4 IS lens will function very well with a 1.4 X extender. It will slow the auto-focus down, but it will still auto-focus. That combinations worked very well for me while shooting wildlife, with the extra bonus of being very close to being a macro lens. The extender doesn't change the close focusing ability of the lens, so you have a 420 mm lens that focuses down to just under 5 feet.

Q: 10. ...and while displaying my novice; can I inquire if this specific lens is compatible with the t4i?

A: Yes. This lens will work on the T4i. It will look like the equivalent of 450mm, due to the APS-C crop sensor, which carries a 1.5x conversion factor. All EF and EF-S lenses will work on this type of sensor.