When connected to a data projector, have you ever found that your circles are elliptical, even though you have “Equal Aspect” clicked on in Autograph?
Most wide-screen laptops are 16:10 aspect, and switch automatically to 4:3 (using 1024 x 768) when connected to a data projector. The problem illustrated here arises with more modern projectors that can handle wide-screen, but usually to the ‘TV’ standard 16:9. The laptop is likely to be in 1280 x 800 (16:10). The solution is to change your laptop (if you can!!) to 1280 x 720 (16:9). Older graphics cards will not offer this, in which case you should switch the projector to 4:3 aspect.