Canon 18-135 ef-s IS lens manual focus

[Ge0ffrey]

Totally newby,
 bought the wife a rebel camera and Canon 18-135 ef-s IS lens.  It's wrapped for christmas but I had the lens out of box earlier, not on camera.   When I turn the manual focus ring it seems to have a short zone of 20 degrees or so rotation where nothing happens, focus ring turns freely  and then the lens extends say and then reversing the rotation the ring rotates freely as it passes thru the dead zone and then the lens retracts.  What's happening?  this is probably a very dumb newby question. 

[Ge0ffrey]

OK, perhaps the so called dead zone is the focus zone and I've turned the focus ring too far if the length of the lens begins to change.  I thought the length of the lens should change when focusing but maybe not the case wirth this lens.

[Bob Atkins]

Are you sure it's the focus ring that you are turning and not the zoom ring? The focus ring is narrow ant at the front, the zoom ring is wide and in the middle of the lens.

See my review here - http://www.bobatkins.com/photography/reviews/canon_ef-s_18-135is_review.html

I know the lens extends when you zoom it. I don't recall it extending when it's focused.