Remove Dust from HDR Images with Cloning
Cloning is one of the most important techniques you should master if you want total control over your high dynamic range (HDR) images. Dust, while not always a problem, is certainly an irritant with dSLRs. The problem is caused by constantly removing and reattaching lenses.
Without the lens on, dust floats through the hole where it was mounted and gets on the sensor. Even if you never take off the lens, the cameras aren’t air-tight.
Dust, which shows up as big blobs on photos, is most noticeable in the sky or other light, evenly toned areas. You might not see it (hence, it won’t be a problem) in more complex areas of your image, such as in trees and grass.
The Spot Healing Brush (in Photoshop or Elements) is the best tool to use for dust in most situations:
Duplicate the layer you want to make the adjustment on.
Select the Spot Healing Brush and set the size large enough to cover the dust.
Paint over the dust spot with a circular motion.
Brush just enough to cover the spot. When you release the mouse button, the new material is applied. Make sure to check that it’s okay.
Sometimes the Spot Healing Brush mangles the texture of an area or pulls in unwanted material to cover the spot (see the final panel in this figure). It should be obvious. When this happens, undo and repeat. Or, if you need more control, switch to the Healing Brush or use the Clone Stamp tool.