Hi Lester,
This is very sharp image :-)
I guess your lens is the one reviewed by Christian Buil here:
http://www.astrosurf.org/buil/testopt/50mm.htm
here:
http://www.astrosurf.org/buil/us/10d/testopt.htm
and here:
http://astrosurf.com/buil/50mm/test_us.htm
I think most later standard EF lenses are based on older design (like 50mmf1:1.8) so mine must be OK as well (or so I hope :-) )