Is this considered an upgrade?

[sin77]

Sell away Tamrom 17-50 f2.8 (BIM), buy Sigma 18-50 f2.8 OS. Pay around $200 more.

To be used for events on D7000 and D5100.

 

[catchlights]

do you think the photos can tell the differences?

 

[sin77]

eh,,,, thinking whether worth to get stabilized lens. Tamron is noisy and hunting when focusing.

 

[Blur Shadow]

Well, if you prefer to have the OS function, then just go for the Sigma lor. $200 only. Quite good. Plus, I am assuming you are selling a well used lens to acquire a brand new Sigma.

 

[undergrd]

If the capabilities/functions of the Sigma is required in your style of shooting, then it should be worth the switch.

 

[Edwin Francis]

Lens choice is a pretty personal thing. OS? Do you regularly shoot at low shutter speeds at events? I don't, so it wouldn't matter to me - subject movement is more of an issue, and image stablisation doesn't help there.

I don't particularly like the Tamron -- it's a little lacking mechanically. Have no idea about that particular Sigma.

Personally, I'd only bother with an 'upgrade' to the Nikon 17-55/2.8. IMHO (and this is pretty subjective), Nikon flash exposure is more accurate with original Nikkors than 3rd party lenses. It varies -- when I used a D90, I had to regularly change flash exposure compensation when I switched from the Tamron 17-50 to a Tokina 11-16. Seems to be a non-issue on my current all-Nikon setup.

 

[alwaysjerricky]

I take it as you looking for the Sigma 17-50mm lens? OS is good for lens if you need it or maybe you can buy a flash light instead to help take faster pictures (if that's what you want).