Hey guys. It is the most annoying thread "poster" you know. I have a sigma 28-70 f2.8-4 lens. When i take photos with this lens, the results ... are never satisfying. I REALLY want a Canon 17-85 USM IS lens or the Tamron 17-50mm f2.8. I was thinking that the canon might be the better bet. Only reason i am thinking this is because whenever i use a lens with a wide aperature the focus sometimes is too soft or if i wish not to create a shallow DOF and keep the shutter open longer, the results are blurry. (if im saying this correctly) Possibly the IS in the Canon will help when taking photos in lower light more than a wider aperature? I wish not to use a tripod, and the hardest thing is to keep the camera still. I realize the Tamron might be better glass, but what about when i want more in focus and a less shallow DOF? I have a 50mm 1.8 .... maybe the Canon 17-85 is the way to go? What do you think? ... p.s. I dont like to use flash or raise ISO too high.