Hi all,

Gary wrote:

>  But I could occasionally  hear some rubbing noise when I had moved the
> lens up and down with IS at 135mm.  I don't remember I hear that with the
> other two... could it be this lens is extra new?  Not sure.  Any
thoughts?

My lens sometimes does something I believe is the same as you are
describing: it makes a strange vibrating/rattling noise when I move the
lens with IS engaged. I believe this is normal. According to me this is
what happenes:
When you move the lens a little bit with IS engaged the IS-lens-element
will try to counteract your movement so that the image in the viewfinder
will remain the same. If you move even further in the same direction the
IS-element will also move futher to the side, to correct for your larger
movement. But at a certain point the IS-element has moved so far up to one
side of the lens, that it reaches its limits and hits the inner side of the
lens. At that point the IS element must jump back to the center position
(the image in your viewfinder will, of course, jump also). Keep on moving,
and a little while later the IS-element has again reached its limits and it
will then, again, jump back into the middle. This makes the
vibrating/rattling noise. Since at 135 mm smaler movements of the lens
require larger corrections of the IS-element, you are more likely to hear
this noise.
With regard to your not hearing this sound with the other two lenses: I
could imagine that there are different versions of the lens in circulation,
since Canon probably has adapted/improved the IS-lens control algorithm
over the past years.

Just my 2 cents. Regards,

Bart


*
****
*******
***********************************************************
*  For list instructions, including unsubscribe, see:
*    http://www.a1.nl/phomepag/markerink/eos_list.htm
***********************************************************

Reply via email to