If you own a DSLR, you've no doubt already experienced the annoying problem of getting dust on your image sensor. Dust reveals itself as small dark specks of various shapes in the light-toned areas of your images--typically the sky. Manufacturers are getting pretty creative at adding features to solve the dust problem (such as sonic vibrators that literally shake the dust off the sensor), but it's still an annoying problem for most DSLR users (especially older cameras without anti-dust features). If you look in the areas in red circles in this shot of Merrick Butte (in Monument Valley) you'll see typical dust spots.
Getting rid of dust spots in Photoshop (or Photoshop Elements) is very simple, using either the healing brush or cloning tool. I prefer to use the healing brush tool because essentially what this tool does is to copy the textures and tonal values of the area you're healing "from" to erase the dust spot. You can use the cloning tool, but you run the risk of disturbing the tones or textures of the area you're patching and if not done well, you can create a fix that's worse than the original problem. And remember, dust never shows up in detailed areas (a grassy lawn, for example), it only shows up in large blank areas.
The best way to solve the dust problem is to avoid it in the first place. Here are several tips you can use for preventing dust getting to your sensor:
- Turn your camera off before changing lenses. The static charge created by leaving the camera in the "on" position draws dust to the sensor.
- Try to change lenses in a car or building where there is no breeze or blowing dust. In dusty areas like the desert, I carry an over-sized zipper bag and changes lenses in the bag.
- Always point the camera body down so that nothing falls on the sensor.
- Be careful to match up lens-mounting index marks so you're no "scraping" the lens on the flange which creates metal shavings that fall onto the sensor.
If you do get dust on the sensor, don't worry too much about it--it's little more than an annoyance that can be easily fixed in editing. Go to your local camera shop and ask for a demonstration on how to clean the sensor yourself and spend the money to get a good quality dust removal tool.
It probably is tough to see online (the compression tends to obliterate tiny details) but here is the same image as above with the dust removed using the healing brush in Photoshop CS3.
