Detecting a small breast cancer tumor
This is a good example of using the contrast setting of Pixcavator's to get what you want. Certainly, the tumor is so small (early stage) that it would be ignored if you use a high setting for size. Fortunately, it brighter than the rest of the tissue. Moving the contrast slider to 100 or so leaves only the tumor captured. The second image is the result of image simplification.
Other image analysis examples