I'm looking to buy a tele zoom, and was set at the amazing Canon 70-200/2.8 II, mostly for shooting indoor/concert type photography. But since its such an expensive lens I thought I'd check if there are any alternatives.
After reading up on lenses, the Tamron 70-200/2.8 Di VC stood out. According to DxOMark it has even slightly better optics than the Canon, and reading through user reviews it seems to have a fast and accurate AF. At ⅔ of the price.
Can anyone shed some light on these two lenses? Is the Tamron comparable? Preferably someone who has used both or done a bit more research than I have :)
I don't recall which it was, but I believe it was DXoMark that rated the Canon lens substantially under what anyone else did. I do not have experience with the Tamron lens, but I own the Canon 70-200 f/2.8L IS II and it is generally considered the second sharpest zoom lens Canon makes (second only to the 24-70 f/2.8L II).
It is possible that this particular lens from Tamron happens to be as good as one of the top two zoom lenses Canon has ever produced, but I would be extremely surprised if it was. I would certainly recommend looking for further reviews before making a purchase as it doesn't seem to match up with the general consensus about that lens or the relative quality of Tamron vs Canon optics.
I had a similar experience when comparing my Canon 70-300 f/4-5.6 IS to the Canon 70-200 f/2.8 IS II where it didn't look all that much better on paper, but in the real world, it has been more than 4 times better in sharpness, color and general quality. It is quite possible something similar is happening with the Tamron lens.
The thing you have to look at with DxO is the individual data, not the overall "DxO Mark Score" that seems to weight things like minor differences in T-stop heavier than things like significant differences in sharpness. Even at DxO The Canon tested a bit sharper overall than the Tamron, especially wide open on the long end which is where most 70-200mm zooms tend to be used the most. Distortion and Chromatic Aberration are fairly close between the two in the shorter focal lengths, but at 200mm the Canon clearly outclasses the Tamron at f/2.8. The fact that the Tamron transmitted 0.2 T-Stop more light than the Canon wide open is what gave it a higher overall score. It is quite possible that the single copy of the Canon lens DxO tested was not perfectly calibrated, and the Tamron copy was.
Other reviews I've seen put the Canon EF 70-200mm f/2./ L IS II even further ahead of the new Tamron 70-200mm f/2.8 SP Di VC in terms of sharpness, contrast, and color. Look at this comparison at The-Digital-Picture. Most technical gurus that have looked at both lenses place the Canon "II" well ahead of the new (as of 2013) Tamron and Sigma offerings, which in turn are both better than the older 1995 designed Canon EF 70-200mm f/2.8 L and even the 2001 Canon EF 70-200mm f/2.8 L IS.
Don't buy the Tamron. The sharpness and anything else are quite good, however the build quality is not. I have one, the Tamron SP 70-200mm VC USD. I bought it last month. At second day I used it, the AF didn't work. I asked for a replacement. With the new lens, I got a jumping lens everytime I focused. I sent it back again and asked for replacement. Until now, I haven't get any replacement. Bad bad bad build quality. Better for you to buy the Canon 70-200mm L IS ii USM.
I have used both lenses for wedding shoots, sports and animal events using the Canon7D and the Canon 5D mark 3. Both lenses produce excellent quality shots, but there is one big difference between the Tamron and the Canon. While the Tamron produced excellent "posed" shots, it failed time after time when attempting to capture active sports or animal shots. It was very frustrating to have lost some very quality shots when the Tamron failed to consistently track and stay focused for moving subjects. The Canon was able to keep tracking the moving subjects accurately resulting in no loss of photographic shots. If you are only using the Tamron 70-200 Di VC lens for still shots, the Tamron is a outstanding lens and I would highly recommend it. However, if your subjects are moving horizontally or towards/away from you, you will want to invest in the Canon 70-200 f/2.8L IS II lens. The Canon lens simply performs better overall.