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Question: Is this a USA lens, with Sigma's 3 year USA extended warranty, or is it a "grey market" item?
Document: I just called and i will be returning this lens today, and if i get one that works,.. i might upgrade my review, but for now i think this is a fairly fair review for this lens and the troubles it has caused me within 30 days of purchase.UPDATE: I decided to give a slight upgrade to this review. Apparently the blank shots where coming from my camera. I literally shoot 1,000 pics everyday throughout the year n using ur camera that much could lead to shutter problems thank goodness it's still under warranty.
I wanted a nice F2.8 70-200 lens every since my son was on the wrestling team and the low light of the gym made a lot of my pictures grainy. I did my research and narrowed my choices down to the Canon L series F2.8 70-200 IS II and the Sigma F2.8 70-200 with OS. The Sigma is over $1000 cheaper and comes with a 4 year warranty instead of Canon's 1 year. I have saved for over a year and recently bought my Sigma lens and want to brag about it!First and foremost, the pictures I am able to take are amazing.
I've had the Sigma f/2.8 70-200mm for almost two years. I admit it isn't on my camera all that often, but I should use it more. It is heavy, quite large, and certainly restrictive for the close range. But under certain circumstances this is truly a great lens for the price.I've taken some very pleasing photos with the Sigma. The bokeh is wonderful. The lens is sharp enough to please me, and sharp is a top priority for me. I can be 30 to 50 feet away from my 3-year-old grandson and get some really great shots.
.....this is pretty much what I got out of the package provided from a company called Cellular Stream. I don't know about you but I think a used thousand dollar plus change item should not be in poor condition. Basically, the lens would not focus either in manual or auto settings on my camera(camera is in perfect working order), rendering the lens useless. On top of that everyone should be aware that Amazon will try and stiff you with the shipping charges up front upon returning an item that costs a thousand dollars(I'm also a Prime Member).
I will say when I called customer service and complained they will get 4 stars for immediately sending me another shipping label that made my shipping free for returning the item.. Amazon also gets one star for not doing that in the first place. Cellular Stream's quality control for a used item is not very good. You would think they would probably test the lens to see that it works properly.... Now my Canon is pretty common and has not had a problem focusing with any other lens. On top of that I immediately bought the same lens(new) from Amazon which I give 5 stars and guess what?
I bought this lens 45 days ago, and it is really well built, it feels solid, focusing is accurate and fast on my Canon 7d even with Sigma's 1,4x or Canon 2,0x teleconverter. For portraits is fantastic due is big aperture, and can really be helpful on low light conditions.
Enough...This lens is heavy. Much more so than the Canon 55-250mm Efs lens I'm replacing. So much so that I have ordered a mono-pod to help support it during games and other activities I like to photograph. I do not see this as becoming my "walk around" lens... It is sharp and the auto focus is fantastic. (Same with my other 2 Sigma's) The build quality feel is very nice. There is nothing "Chincey" about it at all.
Sigma's support did offer to calibrate the lens to my camera (24hr turnaround) claiming that the lens was fine and the camera was off (I guess my other 5 AF lenses - 2 which are Sigmas - just happened to balance out the camera's issues ;) ). Given the severity of the AF issue though, I opted for the refund instead (and bought the Nikon VRII).If you're looking to save money and the wide-open performance is something you can work with, give the Sigma a try! Otherwise, the Nikon version is sharper (@ f/2.8), faster, and has a better bokeh.
I couldn't find any real hope that they were coming up with a competitive version anytime soon. some site with a patent application wasn't enough to give me pause to wait. sorry local shop and tamron corporation.Sigma's lens OS 2.8. After a few hundred  shots and changing out with my nikon 70-300 during evening soccer games I can say this is money well spent. I made the right choice for me. very solid build. I'm a bit obsessive with build quality and the sigma doesn't disappoint. the focus ring is smooth and everything is solid besides the hood which jiggles.
I don't tend to use this focal length at its closest focus range so the magnification did not bother me. I don't see myself accidentally removing the collar in spite of the big clown-like knob on the side, so that's not a problem for me either. The lack of a weather seal IS mildly problematic for me - I don't generally pull out my equipment during a heavy rain, but it would be a nice 'just-in-case' feature; and I do wish that Sigma had added that to this lens.The things I additionally find to be either problematic, or at least 'quirky,' include the placement of the zoom ring outboard of the focus ring and Sigma's inclusion of the APS lens hood extension.
Answer: Sigma is a renowned lens manufacturer, this lens is probably one of their top of the range Zoom lenses. I bought mine in South Africa and it did come with a 3 year warranty for South Africa. It should be the same for you cause Sigma has operations in the USA.