Hi everyone,

I'm new to photography and may be you guys here can help. I want to buy another lens for walk around lens and also for stocks. Someone's offering me sigma 24-70mm(used) and sigma 28-70mm(new). Should i go for the 24-70 or the 28-70.

Thanks

I would check out reviews for both lenses at dpreview.com.

FWIW, I wouldn't use either. First off, if this guy is parting with the lenses, they aren't going to be anything to write home about.  I know the Canon 24-70 is a lot more expensive, but it is so worth it! 

If the Canon is totally out of the question, and you want to get a budget lens in that range with really good IQ, consider the tamron 28-75 xr di, which has a great reputation, and is considered by many to be comparable to the Canon L. 

I agree with Lisa.
Sigma lenses are not that good IMO. I had the 24-70 some years ago and I sold it right after a few months. Unless my lens was faulty, I experienced lots of flare and ghosts. Plus, it's not as sharp as canon and you have to push sharpness in post.
The only lens I recommend from sigma is the fisheye, which always finds a place in my bag. But it's not much cheaper than the canon 15mm.
Best,
Diego

Thanks guys for the input. I'll consider that as an option. 

do you have the money? if not buy it (Sigma).. I have a cheap Sigma 18-200 and yes everybody can tell me this and that regarding zoom lens quality, that corners aren´t sharp, sometimes heck yeah but mainly it does the job pretty well.. again if you don´t have the money but a sigma, it will do great pictures also.. I want to buy good quality lenses of course but when you saying you are starting it will be good for sure you can buy a 50mm also for a very nice price and awesome sharpness!