New Lens Advice

[KingNine]

Hey guys, I was hoping to get an oppinion on a lens or lenses to help round out my set up. My body is the T4i and I had the kit 18-55 and the EFS 55-250. I replaced 18-55 with the Sigma 17-50 2.8 to get better low light shots of my daughters on stage as they danced in recitals. Wow it took great pics of them but at the 17-24 range it just blurred almost every photo. After researching some I found out the lens was getting known for the same issue. I was tired of loosing all my good picturs which looked good on the little screen but were terrible after I brought them into the computer. Too many shots of my daughters as they left for a dance were gone. I purchased the Canon 24-105 L used from a photographer and took it with me to DC this past week. I loved it so much the 55-250 never got attached to the camera although I could have used the extra reach a few times. (I didn't carry my bag with me as I was chaperoning a school trip and had to choose one lens to bring) I have not had the opportunity to take a portrait style picture with it yet such as my daughter and her date leaving for a dance but I will this weekend as she is about to gradutate. I loved the 2.8 of the Sigma and was wondering just how much trade off for a bokeh effect I'll see if and when I use the canon at 4.0? I've considered purchasing the nifty fifty but at 50mm will I need to stand too far away indoors to get shots? My problem with the Sigma was the lower focal length and that was way below the 50 it extended to and obviously where I was forced to stand in my house or the other locations I used it. Is there anything in a 17-30 range ish that would serve a better purpose than what I currently have? I'm a fan of Imagae stabilization and autofocus. I'm also a fan of saving my money lol. I feel the dance recitial coming up the following weekend will be served well with the canon 24-105 as will taking pictures of her walking the stage this weekend. 

Edit: I might one day upgrade to a FF body so I'd take that into consideration when I"m looking.

[Waddizzle]

" Is there anything in a 17-30 range ish that would serve a better purpose than what I currently have?" 

If you want to stick with full frame EF lenses, then the EF 17-40mm f/4L USM lens is a choice to consider.  While it doesn't have Image Stabilization, I don't think IS matters as much on a wide lens as it would on a longer telephoto.  If you  really want IS, then the EF 16-35mm f/4L IS USM is an option.  I use the EF 16-35mm f/2.8L II USM, which doesn't have IS, and don't miss it, either.

[ebiggs1]

"I use the EF 16-35mm f/2.8L II USM, which doesn't have IS, and don't miss it, either."

Me either. I don't buy any lens because it has IS.  If two lenses are identical with one having IS and the other not, I will choose the one with IS.  But if a lens doesn't have IS , it doesn't bother me a bit.  No IS is not a deal breaker.