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If they show up on pictures (or if it really bothers you on principle) return the lens - but otherwise it's something to live with. It isn't something you can deal with yourself, at any rate.
If they show up on pictures (or if it really bothers you on principle) return the lens - but otherwise it's something to live with. It isn't something you can deal with yourself, at any rate.
It might be worth checking that its not a spot on the sensor rather than the lens.
I also have the 170-500 sigma and it has dust inside the front element. If i ever see specks on my pix i just clean the sensor and they disappear. I think there has to be a pretty hefty amount of dust inside the lens for it to show up.
I think you make a good point, Joe - there is visible dust on the inner surface of the front element of my old Sigma 135-400mm too, but it has never shown up on a picture.
I have got some fungus in my 170-500, just phoned Sigma to see what could be done. It will cost £74.00 for a clean, providing they don't find anything else, like the lens being marked. I would put up with the speck and use photoshop, for a while at least.
I have got some fungus in my 170-500, just phoned Sigma to see what could be done. It will cost £74.00 for a clean, providing they don't find anything else, like the lens being marked. I would put up with the speck and use photoshop, for a while at least.
If you've got fungus in your lens I think it would be worth paying the money and getting it cleaned, it will only get worse... it's also possible that it could spread from this one into other lenses you may have.
If you have any fungi attaching to the glass then it will degrade your glass, the stuff eats away the lens coatings. I would get the lens looked at just to assess where the organisms got in.