One of the lens aspects I always test thoroughly is autofocus accuracy with consistency being especially important as consistency can be calibrated into accuracy if necessary. And, I generally dread testing 3rd party lens AF accuracy because ... historically, many of these lenses have performed poorly in this regard. It is highly frustrating to spend weeks evaluating a lens and have the AF results reveal a flaw large enough to make people no longer interested in it.
As I shared recently, the Tamron 70-200mm f/2.8 Di VC USD G2 Lens
shows impressive sharpness even at its widest aperture. But of course, that sharpness can only be realized if the lens is focused accurately and most of us rely on AF for that task. And, with the relatively shallow depth of field this lens can produce at 200mm and f/2.8, that aspect becomes even more critical.
While I'm not completely finished with this lens evaluation, I have some good news to report. The image shared in this post is a collage of 100% crops taken from 15 consecutive 200mm, f/2.8 autofocused images, each captured with the lens initially de-focused. If I hadn't told you, you might have thought that I simply copied and pasted a single image to create this graphic, but those are indeed 15 different images. That's impressive. And, I have a variety of similar tests showing similar results.
I had a track meet to photograph last week and ... I really wanted to see how this lens would perform in that role. The Tamron 70-200 made it into my hands just as I was leaving and, (I don't recommend doing this, but I couldn't help myself) without any prior testing, I mounted the lens on a Canon EOS-1D X Mark II
and went out the door. I shot the meet solely with this lens. The results from about 1,000 images captured were not perfect (they never are), but they showed this lens' AF system performing quite well. That I photographed this event in low light, including heavy cloud cover and light rain with a post-sunset ending, gives the results added value.
I often notice peripheral AF points not performing as well as the center AF point when using third party lenses, so I have also been testing those. While the peripheral AF performance is again not as good, it is only very slightly less so, delivering a significant majority of in-focus images, including at the mentioned track meet and even in the very low light levels at that event. A high percentage of the results from a portrait session with this lens, including tightly-framed head shots and utilizing only peripheral AF points, were correctly focused.
So, I'm quite impressed with the Tamron 70-200mm f/2.8 Di VC USD G2 Lens' AF performance.
At this point, this lens is looking like a bargain: B&H
has the Tamron 70-200mm f/2.8 Di VC USD G2 Lens
in stock (Nikon mount in stock soon).