Doesn't this suck dust into the lens body? -jim
> > Aha, great, now I understand the point. This is actually to increase the > efficiency of the hood for entire zoom range. Clever idea. > > Regards, > Alex Z > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Michael J. > Shupe > Sent: Monday, November 25, 2002 10:54 PM > To: [EMAIL PROTECTED] > Subject: Re: EOS 28-70L > > > Alex Zabrovsky wrote: > > > > Heading for the 28-70L I was surprised to discover that the lens extends > in > > zooming operation. > > Is that correct ? (I saw few pictures of the lens in different zooming > > positions and in one of them it shows the barrel extended relatively to > > another one). > > > > Prior to that I was sure besides of internal focusing it features internal > > zooming as well. > > How long the barrel protrudes in longest (or widest) setting ? > > > > Regards, > > Alex Z > > It does extend when zooming, but not in the direction you would expect > (most often zooms get longer as focal length increases). In fact, it > gets longer as you zoom to a wider setting, which causes the front > element to move to a position that is shallower in the hood, that is, a > position within the hood which is just about ideal in terms of hood > coverage at every focal length (the hood is mounted to the portion of > the lens that does not extend, so the front element moves deeper and > shallower in the hood). Most people look on the zooming extension as a > drawback, but it has always been my favorite feature of this lens! > > Mike > > > Michael Shupe > M.J.Shupe Photography > Michigan Tech University > www.northernlightsgallery.com > * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
