I have three things I use on my K100D.
First: the rocket blower, which works for the dust most of the time. Keep in mind that you may actually blow dust up in behind the view finder, if that sort of thing bothers you(dust will eventually find its way there anyway). You could probably skip this step and go directly to the second step. But I would get one anyway because they work great for blowing dust off of lenses too, and they are cheap.
Giottos Rocket Air Blower Review
Second: If the rocket blower doesn't get it all, I go to the artic butterfly which will get whats left, 99.9% of the time.
VisibleDust - Product Page
Third: As a last resort I go to the digital survival kit (
Photographic Solutions, Inc. - Digital & Photographic Cleaning Solutions), which I have only had to use once in the 18 months I have had the camera. I think on the digital survival kit you have to make sure you get the one with the correct fluid in it, as there are 2 different types, if I remember correctly. (I got the cheap one with the 4 sensor swabs)
Anyway, I searched around and there were all kind of suggestion for sensor cleaning with everything from canned air to someone who tried using a cheap medical bulb syringe. In the end I decided it would be better to invest a little in a cleaning kit, than ruin my camera. I shopped around and got all three together for under $100.
Have a good one.
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