I had a chance to go out today and test my new Sigma 18-50 f2.8. I wanted to see how it compared to my Tamron 28-75 f2.8 for sharpness and contrast, and how much of an improvement it is over the 18-55 kit lens. For kicks, I also threw in my 50 f1.8. I shot comparisons at 18, 28, and 50mm at full stop increments between f2.8 and f11.

I threw my samples up on a junk bit of web space I had lying around: http://rain.prohosting.com/jwexler/lens_comparisons.htm

So which do you think wins...?