IIRC ? Can help me find reliable sites ? I saw a lot of sites citing different prices . The Canon official website says that the 17-55 is sold at 1899 . Then how does the Tamron 17-50 fair with the Canon 17-55 ? Thanks
here's a list of shop which you can patronise:
http://www.clubsnap.com/forums/pric...price-lists-singapore-2012-a.html#post7312281
of which i will recommend going to TK Foto, Cathay Photo, MS Color, SLR Revolution and Orient Photo. then there is Click Camera just beside SLR Revolution also.
Canon's official website only gives the standard retail price(SRP), but it will usually be cheaper at the authorised dealers' side.
comparing between the Tamron and Canon, if budget is not an issue(since you can go up to $1.4-ish), just go for the Canon.
i am not saying the Tamron 17-50 VC is bad, in fact it is quite a sharp lens(though it's non-VC brother is sharper) but the AF motor is slow and noisy.
while slow AF does not matter for video since you will MF anyway but it is quite important when shooting still images where you need quick acquisition of focus.
also, the Canon 17-55 is very good in controlling chromatic aberration. it has little to no CA even when you shoot wide open at f2.8.
flare was also not an issue, i never once worried about having the sun in my frame.
i will leave it to you to decide whether it is worth spending 2x the amount for the Canon or not.
i had the Canon 17-55 for almost 2 years and it is definitely a fantastic lens to use.