GMcD
Established
I should add that these were jpegs and I reduced the file size when loading the images to Flickr. Thanks everyone for the advice. You guys are great.
I think the foolproof method of having a dustless digital camera is to have a standing weekly order out for a new camera. I have repeatedly experienced that a new camera will work without a trace of dust on the sensor for about a week. So this will work for one week, 52 times a year.
Otherwise: learn how to dust the sensor. Easily described above in many posts ... But I still prefer option one above: less mess, and no worries ... and you get to know your UPS person quite well.