I've just returned from teaching a photo workshop in Montana, mostly at Glacier National Park. At one point while out shooting I noticed dirt on the sensor in my photos. There's a right way and a wrong way to fix this. Guess which one I chose?

The right way is to get indoors with the right gear and clean it properly. You start by trying to blow it off with a bulb blower, using either the menu choice to lock the mirror up for cleaning, or the bulb setting to keep the mirror up and shutter open (and being careful!). If that doesn't get the dirt off, then you've got a bigger problem because the dirt is stuck to the sensor.

In that case it needs a physical cleaning, which requires either a trip to a qualified shop or your investment in the gear and knowledge to do it yourself. I had the gear, but it was back at the lodge. And with no blower handy, I resorted to a trick I've used many times - my lungs. Now the trick to this is not to spit into the camera. You've got to blow dryly. But this time I spit (I've cropped the image so you can see it well). Oops. Luckily I had a Nikon DSLR, which gives me an option to create a "Dust Off" reference file, which when used with RAW files from the camera and Nikon's Capture software, can remove dust (and spit).

That night, back at the lodge, I gave it a good, careful cleaning (using Visible Dust products), and removed both the dust and the spit. And I doubt I'll be blowing the sensor off with my mouth again for a while.