Steve, this is most succinct and helpful, thank you very much. I am hoping that a local gallery who used to offer screen printing tutorials will start up again later this summer as planned, which would give me a very simple introduction to the screen printing process. In the meantime I will practice creating a suitable image with the line and lith film.
Using a halftone screen sounds intriguing though. I have seen 35mm contact texture screens on firstcall's website for a pretty penny, but that's for a range of other texture screens that I wouldn't use, and only permits the use of 35mm images, which is no good. Any idea where I can get one these days?
Oh and one other thing - you mention screen emulsion requires UV light - will daylight suffice given enough time?