Originally posted by Mortimer I tried using the built in dust alert and sure enough found the culprit. The dust removal utility just seemed to move it around. Blowing air in did not work either. So I bought a Sensor Cleaning kit (the Digital Survival Kit fwiw) from amazon. That did not appear to work either.
I have had good luck with the 'Visible Dust' kit. The brush in it does an excellent job, so I have not had to use the wet cleaning kit. I have a K100d, without the dust mapping or shaking sensor, so I do have to clean it pretty frequently. I found that hitting the brush with a ZeroStat gun (have one with my old turntable!) and a bulb gets all the dust out of the brush, and helps dissipate any static in the camera. Point the camera downward when you do this and hope that it falls out.
Unfortunately, living in Northern AZ and spending a ton of time in Southern Utah, dust is a constant problem. It's also incredibly dry, so static accumulates on everything. I figure I accumulate the most dust while changing lenses, as I don't have good cases for everything, and they do get a bit dusty. I have thought about taking the ZeroStat with me and hitting the backs of lenses with it and a bulb before mounting.
Regardless of what I've tried, I seem to get dust spots every 6-8 lens changes (sometimes a few weeks, sometimes in a couple days... I'm a prime shooter and change way too often). I've made it a point to clean the sensor every time my batteries get charged all the way, and every time I come back from backpacking. It's easier to get things clean when there are only a couple spots instead of waiting for things to build up.
I think the ZeroStat has helped a ton, especially with older lenses that are pretty dirty inside and out. Pretty pricey, though...
Amazon.com: MILTY - ZEROSTAT ANTI-STATIC GUN (BLUE): Electronics