I didn't see the Tamron 28-75mm f/2.8 Di III VXD G2 Lens coming. This lens's predecessor, the Tamron 28-75mm f/2.8 Di III RXD Lens, was an extremely popular, high-performing model that, announced only about 3.5 years prior to the G2 hitting the streets, was still very young in lens years.
Still, the Tamron 28-75mm f/2.8 Di III VXD G2 Lens announcement was attention-garnering, notably promising "significantly improved optical and autofocus performance," with an MTF chart shared to back up the optical performance claim. In addition to the new optical formula was an improved physical design.
The predecessor lens was so popular because it offered a very useful general-purpose focal length range with a wide f/2.8 aperture available over that entire range in a compact, very attractive package, with an equally attractive price. The G2 takes those features to a new level.
Do you like fast, quiet autofocus? This lens checks that box. Do you like sharp images? The image quality this lens delivers is impressive.
If you have a Sony full-frame or cropped (APS-C) format E-mount camera, you definitely want to read this review.
The focal length range provided by a lens is a primary consideration for the purchase of or the selection of use for that lens. Focal length matters greatly because it drives focus distance choices, and those distances determine perspective.
Most subjects can be photographed with any focal length, but not all angles of view provided by those focal lengths are practical from a working distance perspective, and they do not all provide the ideal relational perspective when the desired subject framing is obtained. For example, photographing a group of 15 people with a 600mm lens requires a working distance that might require a large sports field to keep all group members in the frame, and a phone may be required to communicate with them.
The moderately wide-angle through short telephoto 28-75mm focal length range covers a huge range of general-purpose needs, making it an ideal option for photographing a vast range of subjects. This is the type of lens you can take when you are unsure which focal lengths you will need, and it will usually be found to be the right choice.
The 28-75mm range is great for photographing people, and it is ideal for portraits, weddings, parties, events, documentaries, interviews, lifestyle, theater, fashion, studio portraiture, candids, and even some sports. Use 75mm for head and shoulders portraits and the wider end for groups and environmental imagery.
This lens is a perfect choice for media and photojournalistic needs. It is a great option for street photography.
This lens is a good choice for landscape and cityscape photography, with compositions being ideally captured using every focal length available in this lens. It is not difficult to create compelling landscape compositions using the 28mm perspective while still providing emphasis on a foreground subject against an in-focus background while providing the viewer a sense of presence in the scene. 75mm works great for mildly-compressed landscapes featuring distant subjects such as mountains.
With a wide aperture, this lens is attractive for photographing the night sky, with the 28mm end typically being of most interest in that regard.
This lens is well-suited for commercial photography, and the wide end of the range is ready to capture exterior architecture and larger interior spaces. Cityscapes, countrysides, flowers, medium and large products, and much more are in this lens's capabilities list.
Here are two focal length comparisons:
The predecessor and G2 lenses and I spent a considerable amount of time together in many locations.
The 28-75mm zoom range was a great choice for capturing the city.
If you like to photograph your food, this lens covers that.
Going to the beach? This lens is an ideal choice.
Do you like to photograph patterns and details? This lens checks that box.
Many alternative standard zoom lenses offer 24mm on the wide end. Do I miss having the extra 4mm on my general-purpose zooms lens? For landscapes, yes. For event shooting, no.
Here is a 24mm vs. 28mm comparison (captured with a different lens):
On the long end, going to 75mm is more valuable than the to-70mm competitors, but that difference seems small.
On an APS-C (1.5x FOVCF) camera, the full-frame angle of view equivalent will be 42-112.5mm. This APS-C zoom range is lacking from a wide-angle perspective, certainly impacting landscape use. Still, the standard focal lengths are covered, and the long end becomes considerably more attractive, especially for portraiture.
As of review time, very few zoom lenses have a maximum aperture opening wider than this one, and a wide aperture is a big advantage of this lens.
Wide apertures are helpful for stopping action, both that of the subject and the camera, in low-light levels while keeping ISO settings low. In addition, wide apertures benefit AF systems, enabling them to work better in low-light environments.
While having an f/2.8 aperture may not be greatly advantageous from ISO and shutter speed perspectives when photographing under bright light (daylight for example), wide apertures are useful for creating a strong background blur that makes a subject cleanly stand out, isolated from an even highly distracting background, at any time of the day.
Here is an example of the maximum background blur this lens can produce:
A disadvantage of a wide aperture is the required increased physical size of the lens elements. Larger lens elements come with heavier weight and higher cost. This lens seems to side-step those disadvantages.
Most will appreciate this lens's constant max aperture, enabling f/2.8 throughout the focal length range.
Tamron frequently omits optical stabilization in all of their Di III lenses introduced to date, instead taking advantage of the IBIS (In Body Image Stabilization) implemented in Sony's mirrorless cameras.
In addition to reducing camera shake, the stabilized imaging sensor provides a still viewfinder image, enabling careful composition. Furthermore, sensor-based AF takes advantage of the stabilized view for improved accuracy.
With no IS switch on the lens, the camera menu must be used to enable or disable IBIS, a slight impediment to working quickly, such as when going from tripod to handholding.
As I've said before, a lens's image quality often makes or breaks its success. Tamron's Di III lenses, including this lens's predecessor, have been outstanding performers, remarkably so for their prices. Especially with the Tamron-promised optical improvements, I was anxious to see how the compact, lightweight, and affordable Tamron 28-75mm f/2.8 Di III VXD G2 Lens performed.
In the center of the frame, with a wide-open f/2.8 aperture, this lens delivers very sharp details throughout the entire focal length range. Stopping down produces negligible sharpness improvement, and none is needed.
Often, subjects are not placed in the center of a composition. Moving farther out on the image circle, where light rays are refracted to a stronger angle than in the center, lenses typically show decreased sharpness. At the wide end, this lens produces images with extreme corners that are quite sharp at f/2.8. Lateral CA noticeably impacts corner performance at the long end, though these results are still quite good. Stopping down noticeably resolves vignetting, with little additional change imparted.
The resolution chart is brutal on image quality, so let's take the testing outdoors, next looking at a series of center-of-the-frame 100% resolution crop examples. These images were captured in RAW format using a Sony Alpha a1 and processed in Capture One using the Natural Clarity method. The sharpening amount was set to only "30" on a 0-1000 scale. Note that images from most cameras require some level of sharpening, but too-high sharpness settings are destructive to image details and hide the deficiencies of a lens.
Within the plane of sharp focus, the details in these images are impressively sharp.
Next, we'll look at a comparison showing 100% extreme-top-left-corner crops captured and processed identically to the above center-of-the-frame images. The lens was manually focused in the corner of the frame to capture these images.
Samples taken from the outer extreme of the image circle, full-frame corners, can be counted on to show a lens's weakest performance. The images shown above, captured at relatively long distances, show slight softness, but from a relative standpoint, they are excellent. Correcting lateral CA would improve these results.
This lens does not exhibit focus shift, the plane of sharp focus moving forward or backward as the aperture is narrowed (residual spherical aberration or RSA). Many modern lenses automatically correct for focus shift, though the slight angle of view effects from focus breathing (more later) can appear.
When used on a camera that utilizes a lens's entire image circle, peripheral shading can be expected at the widest aperture settings. At 28mm f/2.8, just under 3 stops of corner shading is present. At 35mm and 50mm, that amount drops to just over 2 stops, with 75mm having slightly more shading – about 2.5 stops. At f/4, the shading numbers drop by about a stop.
F/5.6 corner shading amounts are just over 1 stop, about 1 stop, 0.7 stops, and just under 1 stop for 28, 35, 50, and 75mm focal length settings respectively. Little or no shading resolves at f/8 or narrower apertures.
APS-C format cameras using lenses projecting a full-frame-sized image circle avoid most vignetting problems. In this case, the well-under one-stop of shading showing at f/2.8 will seldom be noticed in images, including those with a solid color (such as a blue sky) showing in the corners.
One-stop of shading is often used as the visibility number, though subject details provide a widely varying amount of vignetting discernibility. Vignetting is correctable during post-processing with increased noise in the brightened areas being the penalty, or it can be embraced, using the effect to draw the viewer's eye to the center of the frame. Study the pattern shown in our vignetting test tool to determine how your images will be affected.
Lateral (or transverse) CA (Chromatic Aberration) refers to the unequal magnification of all colors in the spectrum. Lateral CA shows as color fringing along lines of strong contrast running tangential (meridional, right angles to radii) with the mid and especially the periphery of the image circle showing the most significant amount as this is where the most significant difference in the magnification of wavelengths typically exists.
With the right lens profile and software, lateral CA is often easily correctable (often in the camera) by radially shifting the colors to coincide. However, it is always better to avoid this aberration in the first place.
Color misalignment can be seen in the site's image quality tool, but let's also look at a set of worst-case examples. The images below are 100% crops from the extreme top left corner of Sony a1 frames showing diagonal black and white lines.
Only black and white colors should appear in these images, with the additional colors indicating a presence of lateral CA. Common is for a zoom lens to have noticeable color separation in the corners at the focal length extremes (with a reversing of the fringing colors) and little lateral CA at mid-range focal lengths. In this case, the amount of lateral CA is mild at 28mm, and the color shift crossover is at about 50mm, where little color separation is seen. At 75mm, strong lateral CA color shift is present.
A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light. More simply, different colors of light are focused to different depths. Spherical aberration along with spherochromatism, or a change in the amount of spherical aberration with respect to color (looks quite similar to axial chromatic aberration but is hazier) are other common lens aberrations to observe. Axial CA remains somewhat persistent when stopping down, with the color misalignment effect increasing with defocusing. The spherical aberration color halo shows little size change as the lens is defocused, and stopping down one to two stops generally removes this aberration.
In the real world, lens defects do not exist in isolation, with spherical aberration and spherochromatism generally found, at least to some degree, along with axial CA. These combine to create a less sharp, hazy-appearing image quality at the widest apertures.
The examples below look at the defocused specular highlights' fringing colors in the foreground vs. the background. The lens has introduced any fringing color differences from the neutrally-colored subjects.
Primarily, color separation is showing at 75mm, where it is quite strong.
Bright light reflecting off of lens elements' surfaces may cause flare and ghosting, resulting in reduced contrast and sometimes interesting, usually destructive visual artifacts. The shape, intensity, and position of the flare in an image are variable, dependant on the position and nature of the light source (or sources), selected aperture, shape of the aperture blades, and quantity and quality of the lens elements and their coatings.
On this lens, Tamron utilizes BBAR-G2 Coating to reduce flare.
"Second-generation BBAR-G2 Coating is a groundbreaking advancement that provides vastly improved performance compared to the original BBAR (Broad-Band Anti-Reflection) Coating. The coating corrects for ghosting and flare to an unprecedented extent and renders fine subject detail with true clarity and stunning contrast even under backlit conditions." [Tamron]
Despite the moderately high 17-element count increasing the flare avoidance challenge, this lens shows very few flare effects in our standard sun in the corner of the frame flare test, even when stopped down to f/16.
Flare effects can be embraced or avoided, or removal can be attempted. Removal is sometimes very challenging, and in some cases, flare effects can be quite destructive to image quality. High flare resistance is a welcomed trait of this lens.
Two lens aberrations are particularly evident in images of stars, mainly because bright points of light against a dark background make them easier to see. Coma occurs when light rays from a point of light spread out from that point instead of being refocused as a point on the sensor. Coma is absent in the center of the frame, gets worse toward the edges/corners, and generally appears as a comet-like or triangular tail of light which can be oriented either away from the center of the frame (external coma) or toward the center of the frame (internal coma). Coma clears as the aperture is narrowed. Astigmatism is seen as points of light spreading into a line, either sagittal (radiating from the center of the image) or meridional (tangential, perpendicular to sagittal). This aberration can produce stars appearing to have wings. Remember that Lateral CA is another aberration apparent in the corners.
The images below are 100% crops taken from the top-left corner of Sony a1 images captured at f/2.8.
While the stars are not rendered as perfect circular dots in these examples, these results are quite good compared to those from other lenses in this class.
This is a standard zoom lens, and the usual standard zoom lens geometric distortion description holds true. This lens has barrel distortion at the wide end, which transitions into negligible distortion (at just wider than 35mm) and pincushion distortion at the long end. The barrel distortion at 28mm is modest and the pincushion distortion at the long end is strong. The wide-end distortion amount is good for a lens in this class, and the long-end distortion is relatively strong.
Most modern lenses have correction profiles available (including in-camera), and distortion can easily be removed using these. Still, distortion correction is destructive at the pixel level as some portion of the image must be stretched or the overall dimensions reduced.
As seen earlier in the review, it is easy to illustrate the strongest blur a lens can create. Due to the infinite number of variables present among all available scenes, assessing the bokeh quality is considerably more challenging. Here are some f/11 (for diaphragm blade interaction) examples.
The first example shows defocused highlights being slightly mottled in fill. The nine diaphragm blades are not closing a perfectly equal amount, rendering some sides of the shapes shorter than others. The second set of examples shows full images reduced in size and looking very nice.
Except for a small number of specialty lenses, the wide aperture bokeh in the frame's corner does not produce round defocused highlights, with these effects taking on a cat's eye shape due to a form of mechanical vignetting. If you look through a tube at an angle, similar to the light reaching the frame's corner, the shape is not round, and that is the shape we're looking at here.
As the aperture narrows, the entrance pupil size is reduced, and the mechanical vignetting absolves with the shapes becoming rounder.
A 9-blade count diaphragm will create 18 point sunstars from point light sources captured with a narrow aperture. In general, the more a lens diaphragm is stopped down, the larger and better-shaped the sunstars tend to be, and wide aperture lenses tend to have an advantage in this regard. This lens is capable of producing beautiful stars, as illustrated below.
The examples above were captured at f/16.
The design of this lens is illustrated below.
As I said in the Tamron 28-75mm f/2.8 Di III RXD Lens review, overall, especially considering the challenging wide-angle-to-telephoto focal length range traversal along with the price of this lens, the image quality being delivered by the Tamron 28-75mm f/2.8 Di III VXD G2 Lens is excellent.
"The [Tamron 28-75mm f/2.8 Di III VXD G2 Lens's] AF drive system is equipped with a VXD [Voice-coil eXtreme-torque Drive] linear motor focus mechanism. VXD is exceptionally responsive and operates at high speed with great precision. The AF speed marks approximately twice as fast as the [RXD (Rapid eXtra-silent stepping Drive) used in the] 1st-generation Model A036. [Tamron]
The Tamron 28-75mm f/2.8 Di III VXD G2 Lens focuses extremely fast, and it does so very quietly, audible only with an ear near the lens. Wide aperture lenses are usually great choices for low-light photography, and with an Alpha 1 behind it, this lens can focus on contrasty subjects under dark conditions, with the usual drop in focus speed.
The 28-75 VXD's focus accuracy, the most important autofocus aspect, has been excellent.
While it can be an individual lens-specific attribute, the review lens does not exhibit parfocal-like behavior. If you adjust the focal length, re-establish focus.
The first example provides another look at the wide-open 75mm image quality this lens produces.
FTM (Full Time Manual) focusing is supported in Sony's DMF (Direct Manual Focus) mode with the shutter release half-pressed or the AF-ON button pressed.
Normal is for the scene to change size in the frame (sometimes significantly) as the focus is pulled from one extent to the other, referred to as focus breathing, a change in focal length resulting from a change in focus distance. Focus breathing negatively impacts photographers intending to use focus stacking techniques, videographers pulling focus, and anyone critically framing while adjusting focus. This lens produces a moderate change in subject size through total extent focus distance adjustment.
A single customizable focus stop button is provided. With the camera set to continuous focus mode, press the focus stop button to lock focus at the currently selected focus distance, permitting a focus and recompose technique. This button also acts as a custom button and can be programmed to another function using the camera's menu or via Tamron Lens utility.
FTM (Full Time Manual) focusing is supported via Sony's DMF (Direct Manual Focus) AF mode.
This lens does not have an AF/MF switch, requiring this frequently used camera setting to be changed via the menu system (or with a camera dial on some models) — or via the reprogrammed focus stop button.
The fine-sharp-ribbed rubber focus ring is moderately large in size, and raised slightly from the lens barrel, it is easy to find. This ring is very smooth, has a nice amount of resistance, and when turned slowly, the just under 1080° of MF rotation adjusts focusing at an ideal rate that, aside from a stepping behavior, allows precise manual focusing even at close distances.
This is a variable response MF ring — turn it quickly, and about 230° of rotation will complete the full extent focus adjustment. While I often prefer a linear response MF ring, I did not find the multi-speed adjustment rate to be troublesome with this lens.
With a minimum focus distance of 7.1" (180mm), the 28-75 VXD has a very high 0.37x maximum magnification spec.
|Canon RF 24-70mm F2.8 L IS USM Lens||8.3"||(210mm)||0.30x|
|Nikon Z 24-70mm f/2.8 S Lens||15.0"||(380mm)||0.22x|
|Sigma 24-70mm f/2.8 DG DN Art Lens||7.1"||(180mm)||0.34x|
|Sony FE 24-70mm F2.8 GM Lens||15.0"||(380mm)||0.24x|
|Tamron 28-75mm f/2.8 Di III VXD G2 Lens||7.1"||(180mm)||0.37x|
|Tamron 28-75mm f/2.8 Di III RXD Lens||7.5"||(190mm)||0.34x|
Maximum magnification is achieved at 28mm, where a subject measuring approximately 3.6 x 2.4" (91 x 167mm) can fill a full-frame imaging sensor. The USPS love stamps shared below have an image area that measures 1.05 x 0.77" (26.67 x 19.558mm), and the overall individual stamp size is 1.19 x 0.91" (30.226 x 23.114mm).
It is obvious, even in the drastically reduced image size shared above, is that the f/2.8 corners are super soft at minimum focus distance. In this regard, stopping down to f/11 helps a lot, but the corners remain soft, with strong lateral CA.
At 75mm, a 5.6 x 3.7" (142 x 95mm) subject fills the frame.
The 75mm focal length creates sharper corners than 28mm, but these periphery results are still not stellar at this magnification.
Need a shorter minimum focus distance and higher magnification? Mount an extension tube behind this lens to significantly decrease and increase those respective numbers. Extension tubes are hollow lens barrels that shift a lens farther from the camera, allowing shorter focusing distances at the expense of long-distance focusing. Electronic connections in extension tubes permit the lens and camera to communicate and otherwise function as normal. As of review time, Tamron does not publish extension tube specs or manufacture these items, but third-party Sony-compatible extension tubes are available.
This lens is not compatible with Tamron teleconverters.
"The all-new 28-75mm F2.8 G2 incorporates a new design that becomes the hallmark of TAMRON lenses introduced in the future. Changes to the texture of the zoom ring surface and focus ring surface improve the grip and enhance ease of operation. The surface of the lens exterior is shiny black, much glossier than previous models. Improved abrasion resistance makes the lens harder to scratch and resists fingerprints. In addition, certain internal parts have been enhanced. These advancements result in smoother overall operability. TAMRON has also adjusted the resistance and torque of the zoom ring to facilitate smoother and more precise operation." [Tamron]
The Tamron 28-75mm f/2.8 Di III VXD G2 Lens is shown to the left of the Tamron 28-75mm f/2.8 Di III RXD Lens in the above comparison image – with the new slim rear cap. The changes are quite positive, strong improvements, and overall, the VXD lens design and build quality are really nice.
The lens exterior features engineering plastic construction.
As a rule, standard zoom lenses extend with focal length increase, and this lens extends a modest 0.7" (17.9mm) at 75mm. The 28-75 VXD has negligible play in the barrel even when fully extended.
The sharply-ribbed rubber zoom ring, slightly raised from the lens barrel, is easy to find, and it operates smoothly. The zoom ring positioned toward the front of the lens, in front of the focus ring, places the overall camera balance behind the optimal left hand placement for operating this ring. The 65° of zoom ring rotation is optimal.
This lens has only one button, the programmable focus stop button. Positive is that the lack of switches should mean increased reliability, including a decreased opportunity for dirt and moisture penetration, along with reduced cost.
A USB Type-C port is located near the mount.
Why does this lens have a USB port? The 28-75 VXD lens can be plugged into a computer (USB Type-C cable not included) and managed via Tamron Lens Utility.
Using this software, the lens firmware can be updated, the focus ring direction can be reversed, the focusing ring adjustment rate can be set to linear or variable, and the lens AF stop button can be customized.
The settings available for the AF stop button are:
"For greater protection when shooting outdoors, leak-resistant seals throughout the lens barrel help protect your equipment. Also, the Connector Port is the water-proofed USB Type-C variety." [Tamron]
"The front surface of the lens element is coated with a protective fluorine compound that is water- and oil-repellant. The lens surface is easier to wipe clean and is less vulnerable to the damaging effects of dirt, dust, moisture, and fingerprints." [Tamron]
This Tamron lens is compatible with advanced mirrorless camera features, including Hybrid AF, Eye AF, Direct Manual Focus (DMF), and in-camera lens correction (shading, chromatic aberration, distortion).
Especially from a comparative standpoint, the Tamron 28-75mm f/2.8 Di III VXD G2 Lens is compact and lightweight.
|Model||Weight oz(g)||Dimensions w/o Hood "(mm)||Filter||Year|
|Canon RF 24-70mm F2.8 L IS USM Lens||31.8||(900)||3.5 x 4.9||(88.5 x 125.7)||82||2019|
|Nikon Z 24-70mm f/2.8 S Lens||28.4||(805)||3.5 x 5.0||(89.0 x 126.0)||82||2019|
|Sigma 24-70mm f/2.8 DG DN Art Lens||29.5||(835)||3.5 x 4.8||(87.8 x 122.9)||82||2019|
|Sony FE 24-70mm F2.8 GM Lens||31.3||(886)||3.4 x 5.4||(87.6 x 136.0)||82||2016|
|Tamron 28-75mm f/2.8 Di III VXD G2 Lens||19.1||(540)||3.0 x 4.6||(75.8 x 117.6)||67||2021|
|Tamron 28-75mm f/2.8 Di III RXD Lens||19.4||(550)||2.9 x 4.6||(73.0 x 117.8)||67||2018|
For many more comparisons, review the complete Tamron 28-75mm f/2.8 Di III VXD G2 Lens Specifications using the site's lens specifications tool.
Here is a visual comparison:
Positioned above from left to right are the following lenses:
The same lenses are shown below with their hoods in place.
Use the site's product image comparison tool to visually compare the Tamron 28-75mm f/2.8 Di III VXD G2 Lens to other lenses.
Like so many other recently released lenses, including many Tamron models, the Tamron 28-75 VXD uses 67mm threaded filters. Filters of this moderately small size are affordable, and due to their popularity, they are easy to find and efficient for sharing.
The Tamron HA063 (an "H" added to the camera model number) lens hood is included in the box. This semi-rigid (impact absorbing) plastic hood has a mold-ribbed interior for reflection avoidance. A push-button release to make the bayonet mount smoother is not provided.
This hood's petal shape is optimized to block as much light outside of the image circle as possible. However, lens hoods must be tuned for the wide end of zoom lenses that increase in length with focal length, and the wide-angle 28mm focal length necessitates the HA063 hood to be a shallow design, leaving considerably less than optimal protection at 75mm. The petal shape looks cool and makes visual installation alignment easy, but it does not provide a stable base for the lens to sit upright on.
To state it concisely, the value of the Tamron 28-75mm f/2.8 Di III VXD G2 Lens is exceptional.
What does "Di III" mean? Tamron's Di III lenses are designed for use on mirrorless interchangeable lens cameras. The Tamron 28-75mm f/2.8 Di III VXD G2 Lens is compatible with all Sony E-mount cameras, including full-frame and APS-C sensor format models.
"This product is developed, manufactured and sold based on the specifications of E-mount which was disclosed by Sony Corporation under the license agreement with Sony Corporation." [Tamron] Tamron USA provides a 6-year limited warranty.
The reviewed Tamron 28-75mm f/2.8 Di III VXD G2 Lens was online-retail sourced.
The first question: is the Tamron 28-75mm f/2.8 Di III VXD G2 Lens sharper than the Tamron 28-75mm f/2.8 Di III RXD Lens? Additionally, how do the VXD G2 Lens's secondary image qualities and physical characteristics compare to its predecessor?
In the image quality comparison at f/2.8, the VXD is sharper in the periphery at the wide end and sharper in the center at the long end. The older RXD lens has less lateral CA at the long end and less geometric distortion.
The Tamron 28-75mm f/2.8 Di III VXD G2 Lens vs. Tamron 28-75mm f/2.8 Di III RXD Lens comparison shows the two lenses slightly different in many regards but very similar overall. The design and build of the VXD lens are better. At a similar price, the newer lens seems to be the better option.
The next big question is, should I get the Sony FE 24-70mm f/2.8 GM Lens or the Tamron 28-75mm f/2.8 Di III VXD G2 Lens Lens?
In the image quality comparison at f/2.8, I'm going to give the Tamron lens the advantage in most (all?) comparisons. The Tamron lens has stronger lateral CA. The Sony lens has very slightly less vignetting at f/2.8, and I like the Tamron's flare response slightly better. The Sony lens shows slightly less pincushion distortion at the long end.
Looking at the specs and measurements, the Tamron 28-75mm f/2.8 Di III VXD G2 Lens vs. Sony FE 24-70mm f/2.8 GM Lens comparison shows, as we saw earlier in the review, the Sony being significantly larger and heavier. The filter size difference, 82mm vs. 67mm, follows in this regard. The Tamron has a higher maximum magnification, 0.37x vs. 0.24x, with the caveat that the Tamron lens's peripheral image quality is poor at the minimum focus distance.
Most photographers will find the Sony's additional 4mm on the wide end more beneficial than the Tamron's additional 5mm on the long end. The Sony has an AF/MF switch, a zoom ring lock, and a case included. You could buy a trunk full of cases for the huge price difference. The Sony lens's price is well over 2x higher than the Tamron lens's price. I usually prefer the camera manufacturer brand lens, but I'm having trouble justifying that choice in this comparison.
The Sigma 24-70mm f/2.8 DG DN Art Lens is a good Tamron 28-75mm f/2.8 Di III VXD G2 Lens alternative.
In the image quality comparison at f/2.8, the Tamron lens is sharper in the periphery at the wide end and has stronger lateral CA at the long end. The Sigma lens has less peripheral shading at f/2.8 at the long end and stronger barrel distortion at the wide end. The Tamron lens has stronger pincushion distortion at the long end.
The Tamron 28-75mm f/2.8 Di III VXD G2 Lens vs. Sigma 24-70mm f/2.8 DG DN Art Lens comparison shows the Sigma lens considerably heavier and larger — and it extends nearly twice as far. The Sigma lens has 82mm filter threads vs. 67mm and 11 aperture blades vs. 9. Again, most photographers will find the additional 4mm on the wide end more beneficial than the Tamron's additional 5mm on the long end. The Sigma lens is moderately more expensive.
Use the site's comparison tools to create additional comparisons.
In the RXD review, I said that something doesn't add up, and that statement holds again for the VXD. The comparisons just shared, along with the rest of the review, show the Tamron 28-75mm f/2.8 Di III RXD Lens delivering image quality comparable to the best-in-class lenses, yet this nicely-built, well-designed lens is far smaller, much lighter, significantly lower-priced, and longer-warranted than the premier lens options.
Nearly everyone needs a high-performance standard zoom lens, and the Tamron 28-75mm f/2.8 Di III VXD G2 Lens is a strong contender for the best general-purpose zoom lens choice. The Tamron VXD G2's improved build quality inspires reliability confidence, and this lens is a pleasure to use. The images it produces are even more pleasing.
The Tamron 28-75mm f/2.8 Di III VXD G2 Lens is a very compelling choice for a massive range of general-purpose needs.
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