Sigma vs Canon (Again)

[AndrewEllinas]

I know that this is REALLY old ground but as a new 10D user with only a 50mm 1.8F lens so far -

Are there any proper tests comparing Sigma and Canon lenses available on the web?

In particular comparisons between:

Sigma 20-40mm f/2.8 EX ASPHERICAL, Sigma 70-200mm f2.8 EX APO HSM and the closest Canon L lenses.

User reviews are interesting but too subjective.

Thanks

Andrew

[scottbergerphoto]

"User reviews are interesting but too subjective.

Thanks

Andrew "

Andrew,
You are absoloutely right on this point. Most people have one lens in a given size. If they like it they are going to defend it, especially if it cost alot. L glass is very expensive. I use it and am very happy with it. It would be somewhat disheartening to hear that a lens costing significantly less was better. It's natural to be somewhat defensive on this. You can find a fair amount of lewns reviews on www.pophoto.com and www.luminous-landscape.com
Scott

[bigted]

The best lens reviews I have found on the net come from www.photodo.com. They have a bechmarking system that is well explained and have masses of data from most of the main manufacturers.