Hey guys! I'm a bit new to all this; I'm trying to learn as much as I can so I can start taking some nice shots. I'm looking at a lot of different lenses right now because all I have is the 18-55mm kit lens and a 50mm f/1.8 lens. I use the 50 for portraits and any sort of low lighting photography and I save the kit lens for landscapes and any photos where I can't "zoom with my feet". Does this seem like reasonable usage? I know the kit lens has a shorter focal length so it can capture a wider angle (scenery), and the 50 can take more light in quicker but it has a pretty restrictive focal length. I've been looking around for a decent lens to expand my abilities; I'm torn between getting a macro lens (I would LOVE to take macro pics) and a decent all-purpose lens. I was wondering: What makes the following lens so much better than the kit lens that comes with the XSi? [ame=http://www.amazon.com/Tamron-17-50mm-Aspherical-Digital-Cameras/dp/B000EXR0SI/ref=cm_cmu_pg__header]Amazon.com: Tamron AF 17-50mm F/2.8 XR Di-II LD SP ZL Aspherical (IF) Zoom Lens for Canon Digital SLR Cameras: Camera & Photo[/ame] Do you have any suggestions with regard to a f/2.8 macro lens with a focal length short enough for portraiture? I'm hoping to spend less than $500. Any advice would be awesome .