get a lens with odd number of aperture blades...it'll give you more bursts...as right now the aperture blades cause your rays or whatever you want to call them to be double up...so they're not lining up perfectly to give you those crip shots
if you are happy with the 24-105mm range...you could look at the new sigma 24-105OS....it has 9 blades, and will give you 18 total rays...
also the 24-70mm f2.8'II, 24-70f4IS, tamron 24-70VC have 9 as well
the cheaper tamron 28-75mm has 7
can't justify the $ though.


