Instructable user incoherent, shared an intelligible explanation of his thorough PCB fabbing process along with a bit of background on how it came about.
After experimenting with home PCB fabbing for a while, I’ve finally worked out a process that produces reasonably consistent results that actually look pretty good. I spent lots of time trying to use the toner transfer method with varying degrees of success (OK, varying degrees of failure might be more accurate). I also tried Philmore/Datak negative photo resist spray with consistently horrible results (the stuff eventually melted the spray nozzle that came with it and leaked all over the place). Not Green & not recommended. Now I could have purchased presensitized boards and saved a lot of trouble, but I find the material to be too costly for the volume of boards I’m producing. I eventually tried dry film photo resist and I won’t be going back!
After laying out the board in Inkscape, the dry film resist and artwork transparency are held tightly together in a homemeade vacuum frame and exposed to a bed of UV fluorescent bulbs housed in an old scanner. The funky color gradient soldermask seen in the top pic was actually the result of unintentional overheating during the reflow step. (Note to self: always overheat soldermask.) Check out the full process for Killer PCBs on Instructables.