Hello I am new to this forum and I am sure I am much more of an amateur than the many talented professionals here.  I prefer to shoot portraits and people scenes of  travel photography.

My Canon XTI Rebel Kit lens, the 18-55, broke (actually I have a theory that the security of a recent foreign country airport may have impacted it while I was being thoroughly searched).

Apparently its not covered under my warranty (its only off track) and will cost $100 to be repaired by Canon.  These lenses cost about $150 or a bit more, ballpark, on B&H or Amazon. 

I unfortunately am on a very tight budget, and not keen on paying $100 to fix a kit lens when I could get a brand new one for not much more. 

I found a couple of Sigma  lenses for a good buy and I am wondering what you may know about, and what you think of these lenses? 

Zoom Super Wide Angle 18-50mm f/3.5-5.6
Sigma 28-70mm f/2.8-4.0 High Speed Zoom Lens

 
I would very much appreciate any of your suggestions or help in this area. 

 
Thank you!
 

 What is your budget? I have the Sigma 24-70 f/2.8 and paid under $400 for it. It's not as good as the L glass (I've shot with both and don't see how people can even compare the two) but it works for me for now. It's a very versatile lens for a really good price. I also have a kit lens that is barely used that I would be willing to part with for a low cost. The L glass will come when I have more money!  I was going to list it on E-bay, but I haven't gotten around to it.

Wren,

I think for the most part you will find that the higher end Sigma and Tamron lenses will give you excellent quality for the price.  They will be a big step up from your kit lens.  I would recommend trying to get a constant aperture of 2.8 if possible.  I have a Tamron 17-50mm 2.8 and Sigma 50-150mm 2.8 and have been happy with both of them.

I've switched to all Canon L Glass and am getting rid of some Sigma lenses.  I have a DC 17-70 2.8-4.5 that has been an outstanding lens, and takes very sharp pics.  I'll sell it with a circular polarizing filter and UV filter, and hood.  It's in perfect shape, and I'll throw in a Sigma 70-300 4-5.6 DG that also has a UV filter, circular polarizer, and hood, and a Tamrac padded, zippered storage case.  I used the 17-70 as my walk around lens, and the 70-300 for portraits and longer stuff.  The 70-300 is a decent lens at all  but the longest end where it isn't as sharp as I'd like.  I'll also toss in a Sigma 28-90 Aspherical with a hood that I've never used.  Everything for $325 plus shipping.

Bob Atkins has some great info here:

http://bobatkins.com/photography/digital/10d300dlenses.html

and here:

http://bobatkins.com/photography/tutorials/portrait_lenses.html 

Dave