For normal erasing, use the terrycloth towel. You will notice the markers leave some residue. These should be unnoticeable to the camera and it should never become necessary to interrupt video recording to clean the glass. When in doubt, check the footage. Adjust the learning glass illumination to attain the proper level.
After a week or two of continuous use, it is good practice to deep clean the glass with the foaming glass cleaner and squeegee. Spray the foam across the entire glass, and let it sit for 30 seconds. Starting from the top corner, use the squeegee to wipe horizontally, then move lower to the next patch. Wipe the squeegee with a towel after each pass. Wipe off any residual cleaner on the glass with a clean towel, as you would clean any window.
Our camera will be preset to reverse record.
Yes, the flipped image can be output from a laptop to a flat panel display including a large lecture hall.