Hi Ray, The mask we made from that dxf is working really well for us but we have no experience of using any other so it can probably still be improved. The idea of one to one ratio of bars to spacers was just taken from the on-line generator but letting more light through could be an advantage. At the moment our biggest issue is improving our tracking but we can try some more ideas for masks next time we are looking at focusing. Our "to do" list just grows faster than we can keep up with
Clare & Peter