http://www.adammillerrealtor.com/sigma-camera-lenses-review/

Sigma Lens Vs. Canon Lens?
I am in desperate need of some opinions here…
I am looking for a good lens that I can use in low light situations and for mostly portrait taking. I found these two lenses and from what I can tell there are pro’s and con’s to both of them. I like how the Sigma has a 28-70mm range…but judging by the reviews the Canon has a sharper image. I just feel like the Canon is so limited with it being a fixed 50mm.
http://www.amazon.com/Canon-50mm-1-8-Camera-Lens/dp/B00007E7JU/ref=cm_cr_pr_product_top
http://www.amazon.com/Sigma-28-70mm-2-8-4-0-Speed-Cameras/dp/B00009XVVG/ref=sr_1_106?ie=UTF8&s=electronics&qid=1232134882&sr=1-106
What lens would you choose if you were going to be working on portraits in natural light? (BTW I have a Canon Rebel XTI)
The Canon one will be better because you can use the (larger) aperture for less DOF, and it will give you really nice blurry background.
If your budget allows, the 50 mm f 1.4 will be easier to use. It allows you to adjust the focusing while in AUTO mode. The 1.8, you’d have to switch to MANUAL mode for that. (It is called FTM, for Full Time Manual focusing in Canon lingo).
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