----- Original Message ----- From: "Jim Davis Nature Photography" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, February 17, 2004 1:05 PM Subject: Re: Re: EOS 100-400L How sharp?
> "Skip" <[EMAIL PROTECTED]> wrote/replied to: > > >Focus speed on the 100-400 is pretty slow, remember there's a lot of mass in > >there to move. > > It frankly amazes me how fast it focuses. I usually keep my close > focus switch to 'far away' though so that helps it focus much faster. Fascinating! Two experienced photographers stating opposites about the same lens' AF speed. I too have noticed that my (old) EF 85 f1.8 seems relatively sluggish in comparison with my EF 100 f2.8 USM (over comparable ranges). Others have found just the opposite. I wonder if USM motors gradually gather (very) fine dust as they age, and whether this has a long term effect on AF speed? Some years ago, I met a golfing photo pro who had found his USM lenses had got gummed up by fine sand when he was shooting a tournament in the Gulf States. Since then Canon have improved the sealing on their premium bodies and lenses. Just a thought... Malcolm Milton Keynes, UK www.megalith.freeserve.co.uk/oddimage.htm http://myweb.tiscali.co.uk/ms1938/ * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
