UPDATE 12/21/2019:Please see review updates below leading to this latest update and a change for my review for this filter to 5 stars:First to say Jongsun did an awesome job for supporting a customer with issue on their lens. They stayed in touch with me all the way from China and got a replacement filter to me to test out and review accordingly. Julia there even apologized for the gap of delay due to time zone differences, although that courtesy wasn't needed.After testing over a week with and without this filter using controlled conditions, on a tripod, shutter speeds at least 1/1000 sec or faster. Focus verification on the exact same spot for with and without filter comparison, the images were unedited and un-sharpened RAW images and all looked identical filter on or off, at 600mm. The replacement, although the packaging and filter itself were identical to my precious filter that had the issues, "clearly", (no pun intended) did NOT degrade my Sigma at 600mm, the worst case for the issues I had with soft images and lack of sharpness/detail prior to the replacement.Haze filters that are ruining the Sigma 150-600mm (as well as the Tamron equivalent and the Nikon 200-500mm as well)are out there in forums......it is not chronic, but, then again, not everyone has a super-telephoto and thus, might never see an issue with a lower focal length telephoto.So in summary, the replacement that Jongsun sent me and in only a few days, resolved my issues.The filter is thin profile as many have said, but, no issues on my Sigma. The threads are fine and "dry".....so be gentle threading these on. I typically place the filter on the lens and gently turn it first counter-clockwise until I feel the slight "click" where the correct entry point on the thread alignment are for lens and filter and then begin screwing it in clockwise. this system has always worked well for me; no jams or cross-threading.So in summary, a great filter and a great company who stands behind their product and is willing to bend over backwards to try to resolve issues for their customer. I will be ordering a few more of their lenses for some upcoming new glass some time next year. JONGSUN has earned my continued business. Well done!UPDATE: 12/13/2019. JONGSUN contacted me and graciously provided another replacement for me to test my Sigma 150-600mm Contemporary lens with. That test is in progress and I will update this review accordingly w/i a few weeks . (by end of 12/2019).Given the excellent customer support and effort to try to resolve my issue with a replacement which they have provided, I will state, ...even though my tests are not completed, that they do support their customers 100% and fully stand behind their products.------------------------------------Having had a bad experience where all lens sharpness was totally destroyed using a cheaper 95mm haze with my Sigma 150-600mm, I had hopes this more expensive lens with multi-coating and higher quality glass would do the trick.It did not!Focus was perfect with and then without the filter and like my previous filter, as soon as this JONGSON filter was removed, my lens was back to stellar performance at 600mm.Will try to review forums on line and see who purchased a filter that actually will work fine with my Sigma.The degradation using this filter (like the previous one) is at 500-600mm. Given higher magnification probably maximizes the optical issues using the filter.I think one reviewer got a swap that seemed to work better, but, if this is indeed a quality control issue, (you either get a "good one" or a "bad one"), that scenario would still have me looking for another brand, hopefully a well known and trusted one!Returned it and my search will continue!

The Sony pinch caps seem to hold better than other brands lens pinch caps .I don’t know about canon or Fujifilm but use Nikon and Sigma . Live the new Sigma Magnetic Caps the best . Nikons pinch caps are just ok and the Sigma pinch caps are hard to get on and the square edge on the outside of them let them get knocked off easy . I’ve lost quite a few Sigma Art lens caps by popping off from knocks . The Sony caps hold tight and are shaped not to have an edge to catch .

Bought this to complement my new Sigma lens and it does. Have been out and about taking a number of shots and have ben really pleased with the results - well packaged and quick delivery.

This lens is one of (if not THE) best lens Canon makes, period. It is the premier "sports lens" in the industry, and it has that title for several reasons:1.) BUILD QUALITY: It's built like a tank.2.) WEATHER SEALING: couple with a 1 series body, as soon as it starts raining, everyone else will be scrambling to keep their cameras dry.3.) SUPERIOR OPTICS: color and contrast from this lens are excellent.4.) IS: I bought this lens because of the IS.My former 70-200 lens was the Sigma 70-200 f/2.8 HSM. I'm not going to sit here and lie saying the Canon completely blows the Sigma away- it simply doesn't. The Sigma is a fine lens. It is also built like a tank, the HSM is almost (when I say almost, I mean by milliseconds- ie barely noticeable)as fast, and the colors and contrast are superb- almost indistinguishable from an L lens. There are a lot of "almosts" in this paragraph, I know. The Sigma is "almost" perfect, the Canon IS PERFECT. If you are willing to pay the substantial price difference for perfection, more power to you.The main reason I purchased this lens was not because it was white, not because it has a red ring, and not because it's a Canon. I bought it for the IS. I am a sports shooter and I found myself limited in the shutter speed I was able to use with the Sigma. I am a big proponent of the 1/focal length (x 1.6 on my 30D) rule. At 200mm, I would need a shutter speed of at least 1/320 to prevent camera shake. When using flash, I would have to use HSS for the flash to work at that shuttter speed. HSS significantly cuts down on flash output. I would rather use my cameras maximum x-sync speed (1/250) most of the time. This is where IS comes in handy for me. With the Sigma at 200mm/ 1/250 I would get blurry shots, with the Canon using the IS I'm safe. I can even go several stops slower than 1/250 if I desire. The IS is fantastic and is definitely worth the extra $$$.

I ordered the 52mm filter because the 30mm f1.4 sigma lens for sony e-mount cameras has a 52mm thread but after lens arrived, I couldn't fit it on.But after-service support was pretty helpful in telling me this

This is the first digital camera we have purchased, and are far from professional photographers(I.e. we do not have a need USB charging which appears to be a complaint). It is fairly easy to use once you get the hang of the controls. The Cannon app allows the camera to send images directly to our IPhones, or shoot remotely so that is always a plus. The attached image was a simple point and shoot of the dog and the moon through my cheap telescope.6 Month Update:Absolutely no issues, we have snapped thousands of photos and are getting pretty good at photography now. It is still such a great buy, go ahead and buy if you are on the fence.1 Year In:Added a snap of the Geminids Meteor Shower on Orion’s Belt last night. A long way to go, but slowly becoming competent in Astrophotography with this camera. I would like to branch out with some new lenses this next year. We have been able to document our little boy’s first year of life with this camera, so the investment has been worth every penny.1 1/2 Years:Added the EF-M 22mm f2 lens to up my astrophotography game with this camera and the results are brilliant. It also works as a street prime as well. Camera is still functioning flawlessly. Added a shot of the Milky Way I took last night.Purchased a Sigma 30mm f1.4 lens for beach photography and ended up shooting the Milky Way all night instead. Highly recommend that lens for the EF-M platform because it is pretty much a do-it-all lens.2 Years In:Still absolutely no issues. The Sigma 30mm f1.4 lens pretty much has found a permanent place on this camera after 6 months of shooting with it. Adding the best Milky Way photo I have to date using the Sigma captured at St. George Island, FL.

Let's be clear, this is NOT the best 50mm prime you can get. It's not even great in comparison to them. Arguably, that crown sits atop the new Sigma 50mm F/1.4 Art. Having used the sigma a bit (admittedly, not a lot), it's at least 200% better. Maybe 300% or more, but you'd have to be really adamant about some of the particulars. Make no bones, the Sigma is a tremendous lens. The thing is, it's also an absolute STEAL compared to the former champion, the Canon 50mm 1.2L, $400 more expensive at $1350. If you're following the math, I'm saying this lens is possibly 1/3 as good as a lens that costs nearly 8 times as much, and is already a bargain at that price. There's a reason it's the best selling lens on the market, for any camera system.Yes, your kit lens has 50mm in its range. But F/1.8 opens a whole new world of artistic expression for the beginning or intermediate photographer over the F/5 or F/5.6 that lens opens to at 50mm, and for the price, you'd be insane not to go for it if that even interests you in the slightest. And if $125 is too much to ask for your budget especially if you're a student, get a body $125 cheaper to make room for this lens.

Works very well on my Sigma 17-50 lens. Thank you.