I have T3i and upgrading from my 18-55IS kit lens. I am torn between Sigma 17-50 or Canon 15-85. I do like the extra 35mm of 15-85 for better portraits and street shooting. But then I can also crop the image from 17-50 ??
For indoors, I always use speedlight for better photos. Additionally, I have 50mm 1.8 lens and 55-250mm. My options now:
1) Sigma 17-50mm 2.8 + Canon 85mm 1.8 (sell 50mm 1.8)
2) Canon 15-85mm 3.5-5.6
3) Canon 18-135mm 3.5-5.6
4) Tamron 28-75mm f2.8 (looks good except I read things about inaccurate, slow and noisy autofocus but then again every lens has naysayers)
Since I am using speedlight indoors, would I be fine with 15-85 or 18-135 for parties, family group shots or individual portraits? For outdoors, what's the use of f2.8 ?