[koulang]

[quote name='newboldimages' timestamp='1301952805' post='7375']

Hi

I need some advice -



I use a Canon EOS 500D and will be looking to upgrade to probably 7D in the next year. I did consider 5D mk2 but I mainly do sport photography & concluded that whilst not full frame the faster motor-drive, cropping factor and number of focussing points (I thought) were more of a benefit than the full frame....?



I own a Tamron 10-24mm 3.5-4.5 and a 100-400L series zoom & I want to replace my standard Canon zoom 18-55 3.5-5.6



I am looking at either the Sigma 17-50 2.8 EX DC OS HSM or Sigma 17-70 2.8/4 DC macro OS HSM. I was thinking about the limitation of going with digital only lenses & also I was wondering about macro facility and would it be any good on these general purpose lenses?



I need it for general shots including squad shots of players, landscape, portraits etc



I keep reading conflicting views.



I was thinking it would cost me c £500



I have read the 17-50 is very good but is it any better than the 17-70 which is much cheaper.



Have I overlooked a great quality lens?



Any strong opinions out there?

[/quote]

I own the Sigma 17-50mm F2.8 with my Canon 500D. This lens is very sharp, but you have to make sure that your copy is good one. I experienced with the first copy of my lens was sharper than my second copy especially at frame edge even at the widest aperture, but I returned it back because its focusing accuracy was error. Before I bought this lens, I also tested Sigma 17-70mm OS at the shop and did a rough comparison. I found that the 17-70 lagged far behind the 17-50mm especially wide aperture.