Choosing a new lens

I’ve been doing a lot of event photography since I’ve been in Southampton, and whilst my new Sony A77ii (unusable at ISO 6400 and above) has a lot better ISO quality than my Sony A58 (unusable at ISO 800 and above) did I’m finding that I require, or rather want a new lens.

I currently use a Sigma 24mm F/2.8 lens (the only other lens I have is the Sigma 100-400mm F/4.5-6.5, highly unsuitable for event photography).

I also sold my portrait lens (Sony 50mm F/1.8), and am looking for a replacement for that at the same time.

I require a lens with a low aperture, such as F/2.8 or even better F/1.8 and something covering a range of 24mm to 50mm. I like having quite a wide angled lens as I have a cropped sensor DSLT and the wide angle lets me get more creative with my images.

I have found the following two candidates that seem to fit both requirements of a portrait and event lens.

Sony 16-50mm F/2.8 (Purchased 10th December)

Sigma 18-35mm F/1.8