To clean a microscope objective lens, follow these steps: Remove the objective lens and place it on a flat surface with the front lens facing up. Fold a piece of lens tissue into a narrow triangular shape. Moisten a pointed end of the tissue with cleaner and place it on the lens, then rotate the lens in a corkscrew cleaning motion. Roll up more lens tissue and tear across to create a brush-like end. You should never clean in a circular motion, instead brush across the lens, then use another piece of tissue to remove moisture. Try to avoid using abrasive or lint clothes, and never dry-wipe lenses. This can lead to scratching.