To 2mm less

Looking for an ultra wide angle, I hesitated between it and the Canon 10-22, mainly because of the weight of the lens (the Canon is much lighter, which may had some significance when you have to carry multiple goals on his shoulder ...) but also because of the difference of only 2 mm, which did not seem major. I finally opted for the Sigma and am delighted with this decision because these are the strength 2mm precisely this goal. In practice, the field difference between a focal length of 10mm and 8mm focal length is actually much larger than would be assumed these 2 small mm (growing exponentially), and offers access to a new area of ​​photography to explore.
The Sigma 8-16 is apparently the only goal of the market to offer this extreme zoom range while maintaining superb image quality and virtually no distortion. And too bad for weight.