Just a word here for M. Reichmann with regard to Jay Maisel's close-up enlargements.
You say: "Possibly there's a bit more shadow detail in the Canon frame though (look at the iris). "
I think it's not the iris but just the reflection in his glasses which is slightly more to the left in the Canon shot thereby "drawing" what might seem to be detail from the eye rather than off the glasses themselves.
In any case, both wonderful machines and as always a refreshing article, thank you.

1.) How do you mean by 'slightly more to the left....thereby "drawing"....'?

1a.) Do you mean that the Canon looks like it has more details because the framing is a little more to the left?