I've got a lens hood marked KLEW83 EW-83 that I believe is for the 10-22.
I'm noticing on B&H's web site that they show the EW-83E as being the correct hood for the 10-22 (and 16-35) which has a slightly different shape to it
Did Canon make a change to the 10-22 hood? If so does anyone know when and why?

