Recently, I reviewed a trinity of zooms for Sony FF cameras from Tamron. You might want to reference that post because it has some useful information that applies to this review as well.
In this review I’ll talk about Tamron’s longest lens for the Sony, FF, Mirrorless camera, the Tamron 150-500mm f/5-6.7 Di III VC VXD Telephoto Lens.
Sony cameras are incredibly popular so it makes sense that a third party lens manufacturer would want to make lenses for such a widely loved camera line. Sony guards its patents well and only allows third party lens makers to access SOME of the camera’s features, but Tamron has consistently found ways to add value, even if they can’t match the Sony feature-for-feature.

I’ve tested the Tamron lens in this class as well as the Sony FE 200-600mm f/5.6-6.3 G OSS Lens.
Other than the $13k, Sony FE 600mm f/4 GM OSS Lens, these are the only two options I know about for bird/wildlife photographers working with the FF Sony E-Mount.
COMPARISON
The two lenses take a different approach to get to the same goal.
The first glaring difference is the Tamron costs $600 less at $1399. That’s retail. You can probably get it for $1199- $1299 when Tamron offers an Instant Savings through retailers. – so the net price difference is really closer to $700. That is huge and reason enough for anyone to justify choosing the Tamron.
But there are areas where these lenses go toe-to-toe, and each has slight advantages and disadvantages and the trick for potential buyers is to determine which features are most important to them and their individual style of photography.
Right after the glaring price difference is the fact that the Sony has 100mm more reach. This is significant. And it’s made more significant by the fact that the design of the Tamron lens does not allow the of use teleconverters, but the Sony lens can work with either a 1.4 or a 2X TC.
The 100mm longer reach is big to me. The ability to use teleconverters? Not so much. Even at its fastest aperture, the Sony is around f/11 with a 2X TC and at the extended 600mm range (where most people will use the TC) the aperture becomes f/13. That’s pretty slow for wildlife and nature photography so I personally cannot see myself caring about the teleconverters.
Another big difference is the Sony is an internal zoom meaning the lens does not extend when you zoom out. The Tamron is an external zoom and does extend out. (Now you’re starting to see why the $700 price difference exists.) The question is, do you care?

I personally would prefer internal but for $700 I can live with external.
The Tamron actually has a couple of advantages over the Sony lens. While it’s not super significant, the Tamron does weigh 5.1 ounces less and is significantly shorter, so it takes up less room in the bag, is easier to carry and gives you significant reach with a little less weight. Maybe 5.1 ounces isn’t much, but it all adds up. And it the Sony can actually weigh a tiny bit more because of the lens foot.
For some reason, Sony did not include an ARCA-SWISS compatible lens foot on the 200-600. The Tamron lens foot is ARCA-SWISS compatible right out of the box.
Assuming you’re like 90% of the photographers who use these lenses, you’re going to care about this. So you need to buy a new lens foot for the Sony (figure $145 for the RRS LCF-102 Lens Foot Assembly – making the price disparity around $850 greater. But wait, there’s more – you also need to add a net 1.2 ounces of weight, bringing the weight disparity up from 5.1 to 6.2 ounces.
This may be no big deal to you, but it’s huge to me because I have a bad shoulder and I feel every single ounce I lift.
The Sony also does not have a zoom lock, but the Tamron does. (Tamron calls this the Flex Zoom Lock mechanism to hold zoom position.)

IMAGE QUALITY
On the Tamron, the optics are very good across the full zoom range. Image detail is excellent, with only a minimal decrease at the extreme periphery. Color and contrast are also very good. The autofocus is fast and very good and quiet. I’d give the Tamron a score of 9.25 in this category and the Sony a 9.75. The Sony focuses just a tiny, tad faster, and is a tiny tad sharper. Otherwise, optically, the two lenses are very close. Both produce spectacular image quality given the price range.
HANDLING
The Tamron is smaller and lighter so it clearly wins the handling race – unless the lens extending when zoomed out really bothers you (it does bother some people) so in that case, it’s probably a draw. Tamron offers VC (Vibration Compensation) image stabilization, and combined with its compact form factor, the lens is very easy to hand hold with excellent results.
LENS CONSTRUCTION
Both lenses are well made, and have weather resistance. I have seen reports that the Sony has SLIGHTLY better weather sealing but I don’t have data to prove it.

CONCLUSION
The specs on the Tamron 150-500 lens are very good.
E-Mount Lens/Full-Frame Format
225-750mm Equivalent on APS-C Cameras
Aperture Range: f/5-6.7 to f/22-32
Low Dispersion and Aspherical Elements
VC Image Stabilization with 3 Modes
BBAR-G2 and Fluorine Coatings
VXD eXtreme-Torque Drive Linear AF Motor
82mm Front Filter Size
Moisture-Resistant Construction
Rounded 7-Blade Diaphragm
PROS AND CONS
Tamron PROS
40% shorter in length
More portable
Better constructed switches
Common (and less expensive) front filter thread (82mm)
Slightly lighter
Arca Swiss compatible tripod foot
Removable collar
Closer minimum focus distance
About $700 to $850 cheaper depends on whether or not you add an Arca Swiss foot to the Sony
SONY PROS
VERY Slightly Better Autofocus
Very Slightly sharper
Works with Sony teleconverters (840-1200mm)
Internally zooming
Slightly Better weather sealing
Higher zoom range
Native
Slightly better image stabilization
On a SONY A1 30fps compared with only 15fps if using the Tamron
Offers a focus hold button
Very slightly less vignetting wide open.

MY OPINION
They are both very good and while the Sony is more expensive, it’s not like it’s overpriced. You get good value there for your money. BUT…
The Tamron price is ridiculously low for all this technology and high image quality.
The Tamron is not a perfect lens but it’s probably better than most of the photographers who are using it. And I do not think the Sony is $600 to $850 better than the Tamron – not even close.
While lots of people have varying opinions, the Tamron was good enough to win a major award. The Technical Image Press Association (TIPA) gave the 150-500mm f/5-6.7 Di III VC VXD the 2022 award for “Best Full Frame Ultra Telephoto Zoom Lens.”
I have owned both and kept the Tamron, sold the Sony. Your mileage may vary, but while I do really miss the extra 100mm on the Sony, all the other stuff like built-in AS Lens Foot, smaller and lighter lens, better close focusing distance and huge price difference make the Tamron my choice.