Dust never sleeps! That's a facetious response with a large kernel of truth imbedded. Unless the camera was assembled and packed in an ultra clean, absolutely dust free environment, chances are good that there was dust hiding in a crevice, just waiting for the application of power to the sensor to help it migrate over. It's also possible that some of the pesky stuff was inside the lens mounting ring. Which means, if you never remove the lens, it may never get any worse than now. But if you don't remove the lens and run the cleaning cycle, it will never get any better, either. A lot depends on the environment you're in, too. In Arizona, my Canons (300D and 20D) were dust magnets and I was running the cleaning cycles a lot. Here in Tennessee, where summer temperatures and humidity levels are numerically equal, dust invasion is almost non-existent.

If you still think there's a possibility that the problem is noise related, try some test shots at ISO 100.

I'd like to see a test shot, so I can compare that to my Nikon D70 dust problems. I've come to accept a certain level of dust, since, when it is moderate, it's a helluva lot less than I had with my negatives and subsequent scanning. Even with dust on my D70 sensor filter, I do less than 1/10 of the spotting I had to do with negs/scanners.

I now clean my sensor filter only if I get more than 5 or 6 minor dust spots. I test for dust by setting the lens to manual and focus beyond infinite; keep my ISO at 200, set the aperture to max (min lens opening) and overexpose by 2 or 3 stops; I aim at my slide/negative light box. This results in maximum sharpness of the dust contours and shows them the easiest.

I clean as follows: lock up mirror for cleaning, keep camera with lens down, remove lens, apply a Giottos Rocket Blower (largest model) powerfully for 5 to ten blows, put camera face up, apply Eclipse cleaning fluid with a Sensor Swab of the right width, follow the instructions carefully, blow off the lens and put it back on the camera. By all means, avoid the Hurricane brand of blowers like the plague; they spew out little rubber particles that cling to the sensor filter like crazy (after I did that, I had to send my camera to Nikon for professional cleaning).

If your zoom lens extends and contracts when zooming, air gets sucked into and blown out of the camera and lens body, and dust is sure to enter at some level.

My son uses a Pentax *ist DS and has only minor dust problems.

Good Luck!

Frans Waterlander
frans2001@netzero.net

A client just sent me 29 digital files to process. He had a "professional" shoot his product shots digitally. Five folders of different size images of all 29 files. Every image had over 30 dust spots on them. It would have involved more than a days retouching. I suggested to the client to get their money back and hire a real professional.

Getting back to your problem with the dust getting in even though you haven't changed lenses. Zooms allow air to flow in and out through the lens when zooming so it isn't suprising that dust got in anyway. You might try turning the camera off and point it down before changing the lens in the future. But dust on the sensor is a problem for digital camera owners that is not discussed enough. Learning to clean the sensor is not the easiest thing in the world, and in a lot of cases might require sending the camera back for repair. Maybe the manufacturers should package two cameras in every box so you can keep shooting even when one is sent back to be cleaned.

Thank you all!

Or, just buy Olympus.
No dust or dead pixels!