[popo]

Comparisons across systems can be done, in part with caution, as many aberrations don't change with the sensor. Things like distortion, astigmatism, coma, and similar to me are more important once the effective resolution reaches some decency level, which I don't think we have to really worry about with either of these lenses.

 

As for the question why Canon models seem to come first, we have to consider the other launch mount - Sigma's own. At least in the UK, Sigma and Canon mounts will be initially available next month, even if in practice no one will stock the Sigma mount. The Sigma mount is said to use the same communications as Canon, so in effect it is exactly the same lens with a different bayonet.

 

Out of interest, would people out there agree with me in the following. If things aren't good enough, you will look for and pay more to get the best you can. Once you reach a "good enough" level, you look to achieve that at minimal cost. There are many other 50mm lenses which are cheaper, but don't reach the "good enough" level for me to consider. The Sigma is very good and still affordable. It doesn't have to be the best.