Canon 24-70 or 24-105 Zooms

I am wondering if the zoom part that extends on a 24-70 and 24-105L gets dust on it if there is some sort of seal on it to prevent the dust/fibres from getting into the lens. Anyone know what I am talking about? Anyone bust one accidently that has a picture of what it looks like behind the red ring?

They are weather-sealed (With a UV filter). If water can't get in, then I hope dust can't get in either.

Its a crazy question but I saw some little fibres trying to sneak in near the red ring on the zoom. I guess the mere fact it collected there says there is something to prevent something from entering.

Vermin87 wrote in post #3294867
They are weather-sealed (With a UV filter). If water can't get in, then I hope dust can't get in either.

A filter won't do anything for the seal between the moving portion of the lens (while zooming) on either of those lenses. That's where micro-sized dust could potentially work its way inside.

All a filter might do (for weather sealing) is keep water from possibly seeping in around the front lens element.

From having taken many water resistant watches (typically water sealed form 30 to 300 feet) I know that water seals do not always keep dust out, and in a watch a dust speck can stop the thing, rather than just make a blurry spot. I have noted though that the watch cases with a greater degree of water resistance do get less crud in them though.

WMS