Tamron 17-70mm f/2.8 VC - The Must Have Lens for Sony APS-C

Tamron has been on a roll releasing lenses for Sony E-Mount cameras the last few years. They’re small, light, and perform great - especially their fast zooms. Recently Tamron announced a brand new lens - the 17-70mm f/2.8 Di III-A VC RXD, their first APS-C dedicated lens. We had the chance to test one out for a few days, read on to see what we think.

Design & Features

The Tamron 17-70mm is a compact lens, coming in at a little under 5 inches long, and weighing just 525 grams. This is a little bit longer and a little bit heavier than Sony’s 16-55mm f/2.8, but you get an extra 15mm on the long end, and the Tamron has image stabilization built into the lens (VC) - a very useful feature for those Sony A6XXX shooters that don’t have IBIS. Like most of Tamron’s E-Mount lenses, the exterior is very simple - you get a large zoom ring, and a thinner focus ring. No distance scale, focus hold button, af/mf switch or VC switch. What you do get is weather-sealing, VC with around 5 stops of stability, and silent autofocus. 

The 17-70mm uses Tamron’s RXD AF motor, which provides high-speed autofocus, and more importantly for videographers, quiet autofocus. Focus breathing is extremely minimal as well. The close focus capabilities of the lens are great, and you can get 7.5” away from your subject on the wide end, and 15.4” away at the telephoto end. The lens also features Tamron’s BBAR Coating (Broad-Band Anti-Reflection) to help suppress flare and ghosting. The optics consist of 2 aspherical elements, a hybrid aspherical element, and 2 Low Dispersion elements. 

Lens Performance

During our tests, the AF performed as if it was a naitive Sony lens. Autofocus speed and accuracy were gear, and the eye-af worked great on the Sony A6600 used for testing it out. Even in lower light conditions, the lens had no issues tracking a horse trotting around. The Tamron 17-70mm is quite sharp throughout its zoom range. Even when shooting wide open, the lens is consistently sharp in the center, and the corners are just a little bit softer around 70mm. Stop down to f/4 and it’s smooth sailing from corner to corner in the entire zoom range.

As with most zoom lenses, there is some distortion present before correcting images. On the wide end there’s a little bit of barrel distortion, on the telephoto end it turns into pincushion distortion. If you’re not shooting a bunch of straight lines across the frame, it’s likely you won’t even notice it. Chromatic aberration is almost non-existent with this lens, especially on the wide end. At 70mm there is a little bit present, but it’s hardly noticeable. The bokeh is nice and smooth, but if the highlights are extremely bright, you can make out some onion-ring effects. 

Sample Photos:

Final Thoughts:

Sony’s APS-C lens lineup is pretty slim, but their crop sensor cameras are quite popular. Many people end up going with a 24-70mm f/2.8 lens as a compromise, but you lose out on the wide end. Sony offers a few APS-C lenses, but in order to get a consistent f/2.8 aperture throughout the entire range, you’re going to have to spend $1,300 on the 16-55mm f/2.8 - a steep price to pay for an APS-C only lens. At just $799, the Tamron has found a perfect balance between performance, quality, and price. If you don’t require a focus hold button or an AF/MF switch, the Tamron is at the top of the chart for mid-range zooms. It’s a great all-around lens that allows you to shoot landscapes, portraits, low-light photography, and more without having to switch lenses. 

The Tamron 17-70mm f/2.8 Di III-A VC RXD can be ordered here.