So as you may know I owned the Tamron SP 70-200mm f/2.8 Di VC USD lens for almost a year. I bought it because it seemed to have all the right specifications. Things like image stabilization, constant f2.8 aperture, weather sealing, even a tripod collar ant it was about half the price of the Canon EF 70-200mm f/2.8L IS II USM. Initially I was so obsessed with bokeh and shooting at 200mm wide open that I supposed I ignored or downplayed some of the issues that the lens had. I even wrote a mostly glowing review about it which you can read here. After a while though it became too much to deal with and I had to part ways with it.
The Tamron 70-200mm vc suffers from something called focus breathing. Focus breathing causes the effective focal length of the lens change depending on the distance from the subject. The result is that 200mm on this lens looks more like 145mm when the lens is at its’ minimum focusing distance. This may not be a problem for everyone but to me it feels like I’m not getting what I paid for. At the end of the day I bought a 70-200 2.8 lens because I wanted to shoot at 200mm at f2.8 not 145mm at f2.8.
The weight of this lens is also something that you have to get used to. Even though it is the lightest of the 70-200 2.8 lenses available with image stabilization it’s still almost 3 lbs. This basically rules it out as a walk about lens.
Then there is the line doubling. This is a phenomenon that made the image look like there was some camera shake involved when there wasn’t. You’ll notice it more as you move away from the center of the image and in the areas of the image that are transitioning out of focus. Granted it’s not noticeable in every single shooting situation, it was most apparent for me when shooting at 200mm wide open.
However the biggest problem was the decentering issues on my sample of this lens. Decentering means the lens elements are not aligned properly. This results in part of your image not being in focus because of a crooked focus plane. Its kind of like what happens in Canon’s tilt shift or Nikon’s perspective control lenses. In the case of the my Tamron 70-200 the left side of the lens was always very soft. Now a lot of the time it was not a problem. I tended to use this lens to isolate subjects so my subject was usually in the centre of the frame which left the sides to fall out of focus. However, if you tried to take a vertical shot or your subject took up the full with of the frame you were inevitably going to get one side blurry, usually the left side. At first I thought a micro focus adjustment in camera would solve the problem but that was not much help. The problem would just to move to the other side of the frame. I used this lens earlier this year to shoot some full length vertical shots of masqueraders in Trinidad and Tobago’s Carnival. Almost all the shots were unusable because of the severe focus shift.
I thought about sending it to repair but after some investigation on the internet I realized that this is not something that is easily fixed. Its certainly not a DIY project and probably not something that anyone without access to factory calibration facilities could possibly attempt to address. This was a problem for me because I bought the international version of this lens which has no warranty. Without a country specific warranty Tamron will not touch my lens. Not even if I pay them!
A bit more perusing of the internet reveled that this does not seem to be an issue with my copy of the lens as it was not hard to find other Tamron SP 70-200mm f/2.8 Di VC USD owners who had the exact same decentering issue. I even saw multiple cases where people got more than one copy of the lens with the same issue.
At the end of the day, considering the design flaws and the quality control issues that plagued my sample I decided that the best thing to do was to part ways with it. Selling this lens brought its own set of issues because Tamron equipment simply does not hold its value like Nikon or Canon.
As of the writing of this post I see Tamron had released a newer version of this lens, the SP 70-200MM F/2.8 DI VC USD G2. However I don’t think I will be buying another Tamron lens in the near future.