Great purchase, easy on the wallet and to use. I’m not sure if it’s a drawback or not but you can’t use your lens hood with this filter on your lens. Kinda I guess.

It does what a polarizing filter should do. Quality... only time will tell. Not sure how "amount" of polarization is measured. Is an image either polarized or not? Sort of polarized? Lightly polarized? Works in the Arctic but not the antarctic? Hmmmm. Perhaps other reviewers would expand on this. From a practical point of view the results are fully satisfactory so far. Good for pics of politicians too using the horns or halos feature.

Pros:- Outstanding sharpness, saturation, and bokeh- USM AF is fast and quiet- 2 focus range settings- Fast f/2.8 throughout zoom range complements 24-70mm f/2.8L- Image Stabilizer- 2 IS modes: 1 - normal & 2 - panning- Weather sealed- Common 77mm filter among L-series- Front element does not rotate with focus- Non-existent zoom-creep (lens does not extend)- Solid construction and feel- Focus range indicator window on top of lens- Comes bundled with lens hood, tripod collar ring, and standalone lens bag- Well controlled vignettingCons:- Heavy- Expensive- Longest of the 4 Canon 70-200mm'sThoughts:Outstanding Lens! Always use a filter and use the lens hood as much as possible. The lens hood does get in the way of using a polarizing filter since the front element does not extend. Front element does not rotate when focusing. One of my more favorite lenses. It is used in conjunction to my 24-70mm f/2.8L. My 1.4x extender is only used when I want more reach, but it does cut the sharpness down a bit. I love the IS on here. The ability to change IS modes is awesome. Having 4 setting switches on the lens is a step up from the 24-70mm f/2.8L (that having none). The white finish on this lens garners a lot of onlooker attention. You'll get a ton of attention at events and need a monopod if you want to use it for a baseball game and the like. 24-70mm f/2.8L seems light after wielding this lens. This lens attached to a 40D will not fit the Lowepro Slingshot 200 in the quick draw position. That said, I never use the included standalone lens bag (it looks more like a tan & black lens holster; comes with a thin black shoulder strap). It's best to get this on sale (Christmas season comes to mind). The $1700~ price tag is steep, but the $200~ in instant rebate is nice.Bottom line:Outstanding Lens! Highly regarded and recommended.

The threading of the filter for the lens cap or threaded hood is not 82mm. I just purchased an 82mm lens cap and hood only to find out it is too large. Looks more like it needs to be a 73mm to 75mm thread. The 72mm thread for my lens is correct, however, and works well.Update 11/4/2020: Ordered a 77mm to 82mm step up ring. The ring fits and means that this is a 77mm thread and not an 82mm thread for the cap and hood. If you buy this filter, you will need a hood and lens cap for a 77mm thread.

While this filter did a good job at polarizing (I was amazed at the lack of glare), I'm really giving it five stars because I dropped my lens face down on a tile floor and the filter cracked--but not my expensive lens. So happy to spend a few dollars to save my $1k+ lens. I'll be buying a new one!

While I have no previous experience with polarizing filters, I’ve always wanted one. I ordered the 58mm diameter filter and it fit my lens perfectly. With the filter installed, I could still put the cap and hood on the lens. The filter turns smoothly to adjust the angle of the polarization. In experimenting with it, the lens did a good job of reducing reflection on the surface of a body of water.

Bought this to use on my Sigma 150-600 where it has performed well. I bought a Canon RF 800mm F11 recently and all my other 95mm UV filters have frames that are too big for the lens hood to be used and I really want to have a UV filter on this lens to protect the front element. I noticed how slim the frame is on this filter so tried it on the Canon 800 and it allows me to attach and remove the lens hood with the filter in place. Perfect. Optical quality is great. Can't see any performance issues compared with my Hoya, Kenro or Marumi filters. This seems every bit as good. It's the only UV filter I've found that has a frame small enough to be able to use the lens hood when the filter is fitted so for anyone with the Canon RF 800 this is a no brainer.

If you are looking for a polarizing filter, this one works well for the kit lens on a Nikon D90.