Actual sun damage is typically more severe than ordinary dust spots. Dust usually appears as faint, soft-edged gray blobs, especially at smaller apertures. Sun damage can show up as obvious burned or discolored areas, and in extreme cases the sensor can be physically scorched. Examples from eclipse/solar-photography coverage show sensors heating enough to smoke and end up visibly burned.

The main risk is prolonged exposure when the sun occupies a significant part of the frame, especially with mirrorless cameras or a DSLR in live view, because the sensor is continuously exposed. Brief exposures are generally much less risky, but for serious solar or eclipse photography a proper solar filter is strongly recommended.