BackdoorArts
Senior Member
I mentioned this in another post, but I thought I'd lay it all out here. I'm a big fan of Sigma lenses, and while I know some have had issues with their customer service department, my lone experience with them when my 150-500mm broke was extremely good with them repairing and returning my lens in less than a week.
My brother, as I've mentioned, is a pro Canon shooter. He had their previous version of the 120-300mm and experienced issues with it not focusing correctly with his EOS 1DX Mk III & IV cameras, but working perfectly with the 5D Mk III's. He went back and forth with Sigma who said it was likely a camera issue, but even after having the cameras checked by Canon it would not function properly on the 1D's. So, when the new version came out, with the ability for you to fine tune the focus across the range of the zoom, he jumped on it, selling his old lens and buying the new one. Same issue. Rather than bore you with all the details I will point you to his blog about the saga if you want to get into just how thoroughly he tested the problem (it also gives you an idea of how cool the new Sigmas are in terms of adjustability).
Saga of the Sigma 120-300 "Sports"
The condensed version, if you don't want to read the blog, is that the Canon 1D's have a different focusing system than all other Canons, and it's probable that the Sigma was not fully tested on all models when developed. This was somewhat acknowledged when my brother took his gear to the Sigma facility in NY and they confirmed the issue and adjusted his lens as best as they could in their lab (in his words, it's now "pretty darn close, but still not right"). They promised to send their data to the engineers in Japan, but he told me he wasn't going to hold his breath to hear anything back from them.
That was 2 weeks ago. On Monday he got a call from the Sigma rep in NY and was told that the engineers in Japan confirmed the issue and were going to custom calibrate a replacement lens for him, which he should be receiving before the end of the year. So, while the jury is still out on whether or not they actually fixed the issue, you have to give props to Sigma for following through so quickly and actually doing something about it. Who knows whether this fix will be slipped into the firmware on all Canon versions of the lens moving forward, but it wouldn't surprise me. I wouldn't expect any announcement since my brother tells me that he's search the web over and over and can't seem to find anyone else who has mentioned this issue with the lens and camera combination, so it's a "hidden bug" for the most part, but one that I would expect to be fixed moving forward.
Seems to me that Sigma is going o great lengths to differentiate itself from the other 3rd party manufacturers, which should have them worried, as well as Canon and Nikon. He mentioned in his blog that he will be getting the 24-105mm after testing it at the Photoplus Expo, as he has never been happy with Canon's and the shots he got there with the pre-production test model were outstanding.
My brother, as I've mentioned, is a pro Canon shooter. He had their previous version of the 120-300mm and experienced issues with it not focusing correctly with his EOS 1DX Mk III & IV cameras, but working perfectly with the 5D Mk III's. He went back and forth with Sigma who said it was likely a camera issue, but even after having the cameras checked by Canon it would not function properly on the 1D's. So, when the new version came out, with the ability for you to fine tune the focus across the range of the zoom, he jumped on it, selling his old lens and buying the new one. Same issue. Rather than bore you with all the details I will point you to his blog about the saga if you want to get into just how thoroughly he tested the problem (it also gives you an idea of how cool the new Sigmas are in terms of adjustability).
Saga of the Sigma 120-300 "Sports"
The condensed version, if you don't want to read the blog, is that the Canon 1D's have a different focusing system than all other Canons, and it's probable that the Sigma was not fully tested on all models when developed. This was somewhat acknowledged when my brother took his gear to the Sigma facility in NY and they confirmed the issue and adjusted his lens as best as they could in their lab (in his words, it's now "pretty darn close, but still not right"). They promised to send their data to the engineers in Japan, but he told me he wasn't going to hold his breath to hear anything back from them.
That was 2 weeks ago. On Monday he got a call from the Sigma rep in NY and was told that the engineers in Japan confirmed the issue and were going to custom calibrate a replacement lens for him, which he should be receiving before the end of the year. So, while the jury is still out on whether or not they actually fixed the issue, you have to give props to Sigma for following through so quickly and actually doing something about it. Who knows whether this fix will be slipped into the firmware on all Canon versions of the lens moving forward, but it wouldn't surprise me. I wouldn't expect any announcement since my brother tells me that he's search the web over and over and can't seem to find anyone else who has mentioned this issue with the lens and camera combination, so it's a "hidden bug" for the most part, but one that I would expect to be fixed moving forward.
Seems to me that Sigma is going o great lengths to differentiate itself from the other 3rd party manufacturers, which should have them worried, as well as Canon and Nikon. He mentioned in his blog that he will be getting the 24-105mm after testing it at the Photoplus Expo, as he has never been happy with Canon's and the shots he got there with the pre-production test model were outstanding.
