This image analysis example came from a nanotechnology company. The goal is "to find the percentage of the bright spots over the total area" in this microscopy image.
The quick analysis I ran with Pixcavator shows that this is feasible. The screenshot below shows the answer at 10.9% (see Pixcavator's output table). For better accuracy of this measurement you'll have to cut off the black area at the bottom. Further, you can move the sliders to capture more of these spots if necessary.
Other image analysis examples