How to remove internal lens dust

I was wondering if it's possible to somehow remove some dust from

inside one of my lenses (EF 24-85mm USM). If it is possible, are any

special tools required? What are the steps to take? If I can't do

this myself, would a normal lens service take care of this?

 

Apoligies if this question has been asked and answered before.

You definitely don't want to undertake it yourself. Even if you manage to get it apart without breaking something, you'll never get it back together properly aligned (collimated)and even if you could, unless you've got a "clean room" you'll probably end up with at least as much dust inside when you're all done. Yes a normal service would take care of it--temporarily. The nature of zooms is such that they tend to vacuum in dust.

<a href="http://photonotes.org/articles/beginner-faq/lenses.html#dust">http://photonotes.org/articles/beginner-faq/lenses.html#dust</a>.

Should of bought a Sigma, no really why do my canon lenses fill up with dust so fast. I think this would be number one canon complaint. I've used to clean my own lenses until I striped a screw. It's pretty embarrassing sending in a lens with a stripped screw.

Actually,modern standard zooms are quite easy to service.Because plastic parts are so easy to make into any shape,there are alot less parts plus ease of manufacture requirements have made most lenses very easy to work on.

<BR>Collimating is not an issue because the elements are either held in a prescision mount or are moulded together as a group-it's very difficult to get them wrong.<BR>What i will warn you about is to only try the job if there is alot of dust-it's EXTREMELY difficult cleaning lens elements to a perfect state!!!

<i>Should of bought a Sigma</i> [sic].<br>Robert, they're no better than any other lenses in this respect and considerably worse in others, e.g. compatibility with future EOS bodies.<p><i>Collimating is not an issue because the elements are either held in a precision mount or are moulded together as a group-it's very difficult to get them wrong.</i><br>Uh, Ron, you won't believe how easily a "precision mount" goes out of whack. And a group that's cemented together goes out of collimation as a whole, that's the only difference to single lens elements in this respect.<p>Jay is correct: cleaning a lens isn't a DYI job unless you've been trained to do it. And bear in mind that dust inside the lens has considerably less impact on image quality than we use to think!

O. S.,

Dust resistance of my Sigma lens outperforms the canon considerably. My 24-70 Sigma gets used the most and I have yet to send it in to be cleaned, but all my canon lenses ,50/1.4, 100/f2, 100-400is and 28-135is are in need of cleaning. In the design 100-400 canon choose to compromise dust resistance, but I have been disappointed with my other canon lenses dust resistance also (all of which cost about the same as my sigma lens). Of course this applies only to high end Sigma lenses.

What i meant with the collimation issue is that in this type of zoom lens the elements (either single or groups) tend to be mounted in such a way as to make it impossible to get wrong.For example whole groups will be moulded as one part which fit into the zoom slots,the focus group will be similar,but fits into the helical.In most cases it's impossible to either get it wrong,or indeed,improve the lens.

I'm not saying lenses should be fooled with willy nilly but the canon consumer zooms do tend to be very simple.I've only seen two examples where a lens element could be removed from it's mount(held in by gum/glue!),both of these were 35-80 cheapies

I know then lenses look like crap when the get dusty and we all want to have nice little jewels for lenses but unless you can see a noticeable softspot in your image why bother? I have use quit a few rental lenses that looked like crap and I never noticed a difference between a clean lens and a dusty one.

 

Because a lens can not focus within itself the dust will not be visable unless its huge. Move on and forget about it unless you see soft spots in your images or hear grinding noises.