Review Tamron 28-75mm F/2.8 Di III RXD (model A036)
The Tamron 28-75mm F/2.8 Di III RXD is a new, bright standard zoom for full-frame Sony E-mount cameras. It is the first zoom lens that has been released by a third-party manufacturer especially for the Sony full-frame cameras with an E mount. It is bright, light, compact and very affordable. With that, Tamron offers Sony photographers an option they have never had before.
Tamron 28-75mm F/2.8 Di III RXD (model A036): Tamron's premier with a Sony FE mount.
The Tamron 28-75mm F/2.8 Di III RXD is the first step in Tamron's strategy to bring more lenses to the market for full-frame mirrorless cameras, such as the Sony A7R III, Sony A7 III or Sony A9. The Tamron 28-75 mm F/2.8 Di III RXD is designed for excellent image quality and beautiful background blur (bokeh). Close-up shots are also possible with this Tamron standard zoom with Sony mount, thanks to a minimum focusing distance of only 0.19m in the wide-angle setting. The usability and versatility of this new Tamron lens are enhanced by its compact size and light weight; it has a length of only 117.8 mm and a weight of 550 grams. Tamron was able to achieve this size and weight by limiting the wide-angle range to 28mm and using plastic. As far as that range is concerned, all else being equal (weight, dimensions, quality, brightness and price), then 24mm is naturally nicer than 28. But that's not how it works. Sony makes a standard zoom with the brightness of this Tamron and a range that does go to 24mm. That zoom, the Sony 24-70 mm f/2.8 Gmaster, weighs more than twice as much, is also much bigger and costs three times as much as the Tamron. So what Tamron has accomplished with the 28-75mm is significant. The Tamron 28-75 mm F/2.8 Di III RXD offers users of the Sony E-mount system an option they have not had before. The promise of smaller and lighter lenses for mirrorless systems is also partly fulfilled.
The design of the Tamron 28-75mm has the modern, fluid lines that are characteristic of all new Tamron lenses. The lens is slim and relatively long. The Sony Vario Tessar 24-70 mm f/4 has a zoom range that is slightly larger but is shorter. The weight of the Tamron 28-75mm is low, especially for a f/2.8 lens. That low weight is achieved with, among other things, the use of a lot of plastic. The lens does not give you the feeling that you can hammer the proverbial nail into the wall with it. However, that does not mean that the build quality is not good. The Tamron 28-75 mm F/2.8 Di III RXD is built with very small tolerances. There is no excessive play anywhere, and everything turns smoothly. The focus ring is very smooth. The zoom ring, which differently than on Sony lenses sits at the front, feels a little bit stiffer, but also turns very well. The lens has no further control elements. No AF-MF switch and no function button. The Tamron also has no image stabilization. That's no problem when you use the lens on one of the newer cameras (see below for our test results for the image stabilization of Sony A7R II with the Tamron 28-75 f/2.8), but it's problematic if you want to combine it with a first-generation A7. The Tamron 28-75mm F/2.8 Di III RXD has a dust and moisture-resistant construction and is fitted with a gasket on the mount. The hydrophobic Fluorine coating developed by Tamron further ensures that the front lens is highly resistant to fingerprints, moisture and dirt. The shortest focal distance is 0.19m in the 28mm setting and 0.39m in the 75mm setting, making close-up shots possible. At 28mm, you get a magnification of 1:2.9, and 1:4 at 75mm.
Sharpness of Sony A7R III shots with IBIS remains constant at 75 mm f/2.8 from 1/200 sec to 1/6 sec.
Modern Sony cameras have built-in image stabilization ("IBIS"), so that - especially for lenses with a focal length of <100mm - the need for built-in image stabilization is not so great. The sharpness of pictures taken by hand at 75 mm f/2.8 1/200 sec turned out to be the same as that of a picture at 75 mm f/2.8 1/3 sec with IBIS. That is a gain of 6 stops! In both cases, the sharpness is already less than that of a shot taken at 1/ 5-stop image stabilization gain.