Focus stacking is a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field (DOF) than any of the individual source images. Getting sufficient DOF can be particularly challenging in macro photography, because it is smaller (shallower) for objects nearer the camera, so if a small object fills the frame, it is often so close that its entire depth cannot be in focus at once. By taking several images, each with a different portion of the subject in focus, and combining them digitally, blurry sections can be eliminated.Photo: Muhammad Mahdi Karim