
Originally Posted by
neuroanatomist
Perhaps it was a marketing decision - in Canon's 'Lens Positioning Article' they state, "While it’s a great match for full-frame cameras, like the EOS 5D Mark II, this lens really comes into its own when used with an APS-C size sensor camera, like the EOS 60D or 7D, or a Rebel series digital SLR." So, the market they're targeting with this lens seems to be people who will probably be used to lenses where the zoom ring is toward the end of the lens. Then again, perhapsthe design was constrained bythe floating element rear-focusing system, requiring the MF ring to be physically close to those elements.