Jenn, in that regard then I would say that there are indeed viable alternatives to the Canon brand lenses. My experience with the Sigma 24-70 2.8 HSM was less than pleasant, however, of the couple hundred pictures I did take with it over the weekend a few were in perfect focus. Those few that were in focus totally blew me away. The optics of that lens proved to be top notch. In fact, I have no problem saying that the optics of that lens was actually quite above that of any lens I currently own. Had I the time and patience I would have had no problem sending it off to Sigma for calibration. For $900, however, I felt that if they couldn't get it right the first time then why should I even bother and that my money would be better spent on Canon's version at a later date.
I feel that Tamron and Sigma both can make excellent lenses, however, when working in a professional environment I feel one should step up and choose professional quality lenses. Canon can produce some duds, and even their own 24-70 (based on reviews I have read) seem to exhibit focusing issues in some copies. However, it does seem that those incidents are lesser than those by off brand lenses. Sigma being the worst culprit based on reviews. Everyone highly regards their 50 1.4 as being a top notch lens, however, people expect to send it back to Sigma for calibration even before purchasing it. I find that to be highly unacceptable that a company be allowed to get away with that or something as pricey as lenses (or anything for that matter).
I guess what it boils down to is whether or not you have the time, patience, and money to not only purchase an off brand copy, but are willing to accept that you may have to try several copies and/or send the lens back to the manufacturer for calibration and wait for its return. I guess what sold me was that I had also ordered the 50 1.4 from Sigma as mentioned earlier, and while it was off I was able to correct for it using the micro-adjustment of my camera. However, I still felt it was a touch off so I sent it back. So that left me at 0 and 2 for Sigma. Canon, however, supplied me with perfect focusing copies of both the 70-200 2.8 IS and the 100mm 2.8L Macro on the first time. It's for that reason I feel the extra money spent up front can save a bit in the long run.
Now, as far as real world suggestions, here's my take with everything being said. Based purely on reviews and what the lenses would be used for, I would take a good long look at Tamron. Their 28-75 2.8 is very highly regarded, and most reviews I have read actually put it above the Canon 24-70 2.8 in just about everything but build quality. With the 70-200 2.8 I would again look at Tamron as an extremely viable alternative. Most reviews compare the Tamron to the Sigma and the general consensus is that the Tamron has better optics, but the Sigma has a better and faster AF motor (due to it being HSM). So if one were doing sports one would choose the Sigma, and if not then one would choose the Tamron. While there could be some moments at a wedding that would beg for a quick shot, and thus auto focusing speed, I think overall I would take quality pictures over faster AF...especially in that environment.
On a side note I re-read my posts and I apologize for its harshness. I have been a bit crabby this morning, and while it was not my intentions it did seem to come out in my posts. There were better ways of stating what I meant without going that route. Again, my apologies.
I do wish you the best of luck, however...you have much more courage than I do. While I have no one I know about to get married or being offered to take such photographs, I would never do such a thing. Weddings are simply where I draw the line.
keep it up
![[No title]](/data/xfmg/thumbnail/37/37609-a1984365804384f841d8245ae7e3b9a7.jpg?1734170735)