Lens fogging up.

[Terry Leach]

I purchased a used Canon EF 85mm f1.8 from a friend tonight. When I got home this evening I took the lens out of my vehicle and into the house. I notice that the lens fogged up really bad on the inside. This puzzles me because it is an inner lens that was fogged up. I know my other lenses will fog over from time to time but only the outter ones. My question is, is there something wrong with this lens? Has anyone else had this problem with this lens? I know the lens was purchased new back in May.

 

[Overread]

Far as I know only some L lenses are fully sealed against the elements (and even most of them require a front filter to be fully sealed). So its no surprised that natural air can get inside the lens itself. Typically fogging of the lens isn't a problem and you just wait for it to match the same temperature as its surroundings. Though a good trick is to keep it in the bag or wrapped in a plastic bag as you move from one environment to the other - that way it reduces the chances for fogging whilst it changes temperature (and since you can't shoot through a fogged up lens you don't really miss out much whilst waiting.

 

[Terry Leach]

Thanks for the info. The lens did have a filter on it and I removed it immediately upon taking it out of my bag because it is junk and was cross threaded on the lens. I will go very soon and pick up a new filter for it. Its been a long time since I have messed with a lens without a filter of any kind on it. I don't guess I ever knew that they done any thing for sealing the lens off. Thanks again.