Sigma vs Tamron 100-400 - which is better

Started 1 month ago | Discussions thread
Flat view
lokatz Regular Member • Posts: 433
Sigma vs Tamron 100-400 - which is better

I'll start with a full disclosure. After months of looking at those two, I bought a Sigma 100-400 today.

I own a Nikon 200-500, which I love and will continue to use. For longer hikes, though, I wanted something lighter without compromising IQ too much. As with most owners, my primary use of these lenses is wildlife and BIF shooting. For that reason, my main selection criterion is how many keepers the lens gives me when shooting hand-held and wide open in mediocre light.

When the Sigma came out, I tested a copy and was amazed how sharp it was, yet disappointed in its poor OS (VR in the Nikon world) performance. When the Tamron came out last November, I did the same and found that the VR was quite a bit better and the AF was actually world-class. However, while the Tammy's IQ was not terrible, it was not nearly as sharp as the Sigma. These tests were conducted under repeatable conditions that allowed me to compare the two with each other and also with other lenses I own or had available for testing (Nikon 200-500, AF-S 70-300 DX and 300 PF, Tamron 150-600 G2, etc.). The Sigma performed nearly as well as a good 200-500, the Tamron 100-400 did not (the 150-600 didn't, either).

As more and more professional and user reviews for both came out, the picture got blurred. Fans of either 100-400 lens argued that theirs got a lot better with USB dock tweaking, Dustin Abbot published his YouTube reviews of both that show each in a pretty good light but shy away from a direct comparison, and on forums such as this one, owners claimed that one or the other was sharper, the primary support argument usually being something like "look how sharp this shot is".

Before arriving at my buying decision, I therefore tested several copies that I could get my hands on. In total, I tested three different Tamrons and four Sigmas. Testing was done with targets 65ft/20m away, as well as at a distance of about 17ft/5m. That's pretty much the range I consider useful for birding - being nearer than that is rare, farther away means you won't get much of a shot anyway. All tests were done on a Nikon D500, with 20 shots in a series, each focused separately, usually with fairly low light, i.e., shutter speeds between 1/15s and 1/350s. ISO was typically between 800 and 1600. Twice, I was able to peg the two lenses against each other directly, the other tests were indirect comparisons. In one case, I repeated a test with the lenses on a tripod, where the IQ comparison was almost identical to the one hand-held.

One of the four Tamron lenses came close to the Sigma I pegged it against, which was the weakest among the three Siggies I tested over time. Just to illustrate how big the differences were: in today's test (40 shots with each lens), the Sigma got 20 excellent and 14 good shots (with half of the tests at 1/15s and the other half at 1/125s), whereas the Tamron got 2 excellent ones and 18 good ones. The best shot with the Sigma is FAR sharper than the best one with the Tamron. All tests were done with identical conditions.

Overall, pictures from both lenses may look pretty sharp when shown full-screen, but when pixel-peeping, there was no doubt across all of my tests which is better. I no longer buy the claims that say the Tamron is super sharp. It is not bad, but the Sigma eats its lunch because of its exceptional sharpness.

Yes, lens variance exists with both makes,so there will be sharp and not-so-sharp copies. I also find it plausible that both can be optimized further with a dock, which I did not do for my tests because I did not want to buy both docks. However, unless Tamron's production process is exceptionally poor and their lenses hit the stores with lousy calibration but become MUCH better when tweaked, which I find very unlikely, the comparison is pretty clear: Sigma wins the sharpness contest hands-down.

I had been tempted for a while to go with the Tamron because of its better AF and VR performance. The fact that it has a tripod collar is almost a don't care for me because I still consider it viable to use the camera's tripod mount with either lens - they're not that heavy. The Tamron's keeper rate, which is what I do care about, though, is quite a bit lower even at slow speeds, which others on this forum also reported. It might have a good image stabilization but unfortunately not always with the subject being in sharp focus. Bottom line: buy the Sigma. Its added advantage is that it is cheaper, which makes it a real steal.

Hope this helps folks who are still undecided about the two.


PLEASE: I'll be happy for you to challenge my findings and will take your arguments into consideration, but only if you also tested at least a few copies and aren't simply basing your arguments on one single experience or a number of "fantastic shots". I am fully willing to assume that a perfect Tamron will beat a poorly calibrated Sigma, but that's not the point. The point is: when buying either of them, what are you LIKELY to get?

 lokatz's gear list:lokatz's gear list
Panasonic ZS100 Nikon D700 Nikon D7100 Nikon 1 J5 Nikon D500 +17 more
Nikon D500 Panasonic Lumix DMC-G2 Sigma 100-400mm F5-6.3 Tamron 100-400mm F4.5-6.3
If you believe there are incorrect tags, please send us this post using our feedback form.
Flat view
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow