Okay. I've been reading about dust mites in lenses. I've seen fungus in lenses. I don't know what this is, but it seems as though I have a shocking 'thing' lurking in my lens. I don't know if it's dead or alive...

It looks like a piece of dust has lodged itself on the back surface of the second element (I'm making a few presumptions there). When the lens is rotated to catch the light, there appears to be a multicolored halo around the speck. Much like a drop of oil in a puddle of water. I am concerned deeply about this. I have had the lens from new, since March 2000. It is just 9 months old.

Can anybody please shed any light on this? I don't think Canon will come to the warranty party as I've only just discovered it...

Many thanks for your replies.

-- Michael King (action_photo_guy@hotmail.com), December 28, 2000

Answers

Zoom lenses in general, and Canon lenses in particular, seem to have a reputation for aquiring dust particles. They seldom do any damage to the images the lens produces. So, unless it's a real whopper, or is very reflective (causing flare), I'd learn to live with it.

Sometimes these really are dust particles from the atmosphere and sometimes they are bits of grease or filings from inside the lens.

From what I have heard, Canon thinks this is just a normal occurance and doesn't warranty dust removal. But maybe if you pressed them real hard, I don't know.

-- Jim Strutz (j.strutz@gci.net), December 29, 2000.

If it does not affect image quality, the issue is a non-starter.

-- Chris Gillis (chris@photogenica.net), December 30, 2000.

I took it to Canon last week. They say it is mould (sure doesn't look like it to me...)and as such, is not covered by material and workmanship warranty. Fair enough, I guess, even if less than 12 months old. They said it would cost $120 ozzie dollars to clean. I just saw a friend's identical (although 6 months older) lens. He has approximately 10 of these nasty little things on the same element (hmmm). Last time he looked he said there was but one.

Since I read various comments from people (thanks), I have been storing it in a clip lock resealable plastic bag with silica gel. It hasn't grown any...will keep you informed.

-- michael king (action_photo_guy@hotmail.com), January 10, 2001.