Sigma 24-70 f2.8 or Canon 24-105L f4

I currently have a T3I with a 28-135 f3.5-5.6 as my walk around setup. I want better glass and these are my finalists. I'm leaning toward the Sigma (already have Sigma 70-200 2.8) but I can get a deal on a used 24-105.

What are you looking for in a better lens? Sharper? IS? Better? Faster? Stronger?

What is your budget?

I'm not sure either of those lenses would be what I would setting on for a crop camera.

This combo is what I use on on a boat while fishing or duck hunting. I have $2500 squirreled away as play money but this set up has a good chance of going for an unscheduled swim. Therefore, I don't want to use it all but I do want faster and sharper.

elcid84 wrote in post #17332025
I currently have a T3I with a 28-135 f3.5-5.6 as my walk around setup. I want better glass and these are my finalists. I'm leaning toward the Sigma (already have Sigma 70-200 2.8) but I can get a deal on a used 24-105.

You are barking up the wrong tree. Both the efs 17-55 and 15-85 will handily outperform the 28-135 on apsc. And both cost less than the 24-105. You need to decide whether your priority is and f/2.8 aperture or a more useful focal length range. I own the 28-135 and the 15-85. The 28-135 is not really apsc-friendly; it is adequate on full frame. The 15-85 is excellent on apsc. I've have never used a 17-55. I shot the Sigma 24-70 f/2.8 at the retail counter. Unless the seller is giving it away, leave it alone. Your 28-135 is better, but not f/2.8.

Why not go with a Sigma 18-35 f/1.8 or 17-50 f/2.8? The 18-35 f/1.8 is probably the best lense you can get on a crop and the 17-50 f/2.8 is a huge favorite (I've owned this lens for years on my crop and I love it). Both have decent resale value if you ever decide to go to FF in the future.

I suppose I should sell off some of my decoy collection and get a full frame body.

No need to go full frame. The 18-135mm stm covers your current focal length (and then some), and would be a big improvement over your current lens with almost all of that $2500 left in your pocket. I've got the Tamron 17-50mm non VC lens, and if you're looking for an improvement in sharpness, it's a lens that can't be beat for the money.