I gave my new 24-70 a workout last night at a preliminary dress rehearsal for our spring Home School Play. There are not many students in the school, so everyone gets involved, and they do a great job.
Because of the low light, I used aperture priority and took the whole evenings group of photos at f/2.8. This is a bit of a step down, since I've been using wide aperture primes in the past, usually at f/1.8 to f/ 1.4.
I was particularly happy that this wide view at 24mm was sharp along the edges with minimal CA's. I did see a few on the edges of the white dresses, but Lightroom took care of them.
I put the vignette on the image, just playing around with the LR settings, its still a preliminary photo since its the first night.
Here is a link to a larger imagehttp://www.mount-spokane-photography.com/Deer-Park/Nicolas-Nickerby/i-5QBDZ2Q/0/X3/Wed-2886-X3.jpg