Tamron 17-50 f/2.8 VS Sigma 18-50 f2.8

dhilberg · Jun 5, 2009

Don't know anything about the Sigma 17-70.

For only $50 more, you get high quality optics in a fast lens with a fixed aperture (f/2.8). Yes, you have a slightly more limited zoom range, but 20mm is really nothing to be concerned about. Just zoom with your feet.

Forget the 17-70 and just get the 18-50 f/2.8 HSM Macro.

delizo23 · Jun 5, 2009

ok cool cool. thanks man. i was about to buy the 17-70. i didnt think about the fixed aperature.

Mr. Murmeli · Nov 21, 2009

Decided to bring this thread back to life...

I was almost certain to buy the Tamron... until I came up with this thread. This is pretty much the only place I've seen the Sigma come up as a winner and was genuinely surprised.

I understand that the Macro version is rather new so reputation pretty much comes from the old generations but I couldn't find any decent comparison made between the newer Sigma (Macro) and Tamron. Anyone better and less lazy at using google? :er:

Also the final recommendation on this thread went to the HSM version, which doesn't exist for Canon (WHY NOT?). So how does the non HSM EF mount Sigma fare here?

Any advice would be appreciated!

Mr. Murmeli · Nov 22, 2009

Ok, sorry about the previous post...

I eventually found a bunch of convenient threads on the Canon digital photography forums.

dhoun · Sep 8, 2011

Quoting from The Digital-Picture.com

'The Tamron 17-50mm f/2.8 XR Di II Lens is very, very similar to the Sigma 18-50mm f/2.8 EX DC Lens. These lenses are more similar than different. They are very similarly sized and shaped. They function very similarly.

The differences? The Sigma flares more easily. The Sigma shows more CA. The Tamron is noticeably wider (17mm vs. 18mm). The Tamron focuses faster but the Sigma focuses more quietly. The Tamron focuses much more accurately - My keeper rate is far higher with the Tamron. My Sigma has a weak left side - For sharpness, the Tamron beats the Sigma easily on the left side, but the Sigma is slightly better on the right. The Sigma rings rotate the Canon direction, the Tamron rings rotate the opposite direction but with less effort. The Sigma is less expensive (but not by much). The Sigma's requires its lens hood to be removed to install/remove the lens cap. My choice would definitely be the Tamron 17-50mm f/2.8 XR Di II Lens over the Sigma'.