EF 17-40 f4L lens dust problem

[Joytek]

I have purchased the EOS 10D and an EF 17-40 f4L lens about two weeks ago. Before that I was using a compact consumer camera without an interchangable lens. I was blissfully unaware of any dust problems and just made sure that the front lens element was clean at all times.

Now it is a whole different story. There are big specs in my pictures. I am quite handy and technically inclined. I have tried to clean the sensor very calrefully with a rubber blower three times already, to no avail.

Now I have also noticed a big pice of dust just behind the front element of the lens. BTW, I am quite a neat person and by no means a slob. I have never taken the lens off outside and when I do so at home I make sure that the work area is very clean.

How can I get the dust spec out of the lens? After having spend so much money (I am not rich) on this equipment I am very down about this.

Could someone please help me with this problem. I love photography but this ordeal has left me at a loss as to what to do.

Thank you in advance.

W.

[ssim]

I end up cleaning my sensor once every other week or so. I do alot of lens switching so you learn to live with that problem. I use a very high powered magnifying glass after cleaning to make sure that I got them all. For cleaning I use a small bulb blower.

I would find it hard to believe that you could cause the dust spec behind the from lens element. There are several lens elements between the front one and your camera. It could be possible that it was in the lens during manufacturing and finally decided to attach itself to the glass element. I would certainly contact your vendor or Canon on this.

[Joytek]

I decided to take matters into my own hands and try to clean the lens. I used a vaccum cleaner to suck on the back end of the lens. The body of the vac was in a different room to prevent stirred up dust from settling.

After a few trys the stubborn piece of dust dislogged itself from the inner surface of the front element.

The method was a bit rude but the moon that night compelled me to immediate action. I love night shots and could not resist going out.

I guess that the SLR cameras are way prone to dust problems and I should have known this when I was buying into this. Nothing in life is perfect.

Overall the 10D and the lens are a great product, delivering very nice quality pictures, so the few quirks aren't so horrible.

w.

[Belmondo]

Have you tried the lens since giving it such rough treatment? If it works, more power to you.....I admire your courage.

Of course, it it's still under warranty, such desperate actions don't involve the financial consequences of doing it to an older lens and having to pull a few pieces of glass out of the vacuum cleaner bag.

Congratulations on apparently solving your own problem.

Tom

[CyberDyneSystems]

Odd that there would be dust in what is advertised to be a "seeled from the elements" lens?

[sdommin]

joytek wrote:
I decided to take matters into my own hands and try to clean the lens. I used a vaccum cleaner to suck on the back end of the lens. The body of the vac was in a different room to prevent stirred up dust from settling.


Yikes!! I'll bet you probably did more to potentially damage your lens (and resultant pictures) by doing that than any speck of dust ever could.

[Joytek]

Well, it seems that the dust speck is gone for good (or at least for now) and the lens is still fully functional. I do agree that it is very odd and disappointing that this "sealed" lens has dust on the inside but I have a hard time believing that Canon would do anything about it if I were to return it. I am a Canadian living and working in South Korea and don't have a warranty center on hand anyways.

I am very hesitant to buy any more lenses becasue I am afraid of problems like this one poping up en masse.

Are there any lenses that are REALLY totally sealed up (even in the backend where they interface with the camera "chamber"?)

w.

[Belmondo]

I don't think your problem is at all typical. It would take a pretty ghastly environment for there to be much concern about getting dirt between the elements of a lens. In your case, I suspect it was something left over from the manufacturing process that dislodged itself after the passage of time. If in fact it is something that found its way into the innards of your lens after you owned it a while, then that suggests to me that you are going places or doing things with the lenses for which they were not really intended, and you just need to be a lot more careful than most other people. I live in the desert, and we have a HUGE dust problem here, and I've simply gotten into the habit of removing the lens from the body, capping the body and both ends of the lenses, and keeping everything wrapped in cloth bags in a Halliburton case when not in use. (Fortunately, dampness/humidity is not a problem here.) Admittedly, it does inhibit spontaneous picture-taking, but it's necessary precaution for the invironment here.

As I said before, I'm glad you found a cure for your problem, and would suggest that you've encounted something unique.....not a likely reoccurring problem.

[David Lawson]

Specs of dust on front elements or filters are always present, it's a dusty world. Behind the element just means you can't wipe it off. The degradation caused by such a spec, especially on the front element is so insignificant to the formation of the image as not to be worried about. Now dust on sensors lets not even go there as its the biggest debate before or since Iraq.

[CyberDyneSystems]

Mt 10D had a large curled strip of magnesium body shaving inside it. From machining the front opening for the lens I assume.... :D

QC?