This is a video running at 4X speed, illustrating the etching process I'm using. The paint is removed from the copper-clad PCB in an Epilog laser cutter. After a wipedown with alcohol to remove any paint dust, the PCB is etched in ferric chloride solution.
Lasering an smd jig.
I sprayed the copper-clad with flat black paint, trying to get a thin, uniform coat. Then I used an Epilog 45 watt laser to raster-engrave at 100 speed and 50 power. There was some paint residue on the etched areas, which was easily wiped away with rubbing alcohol. Overall detail is very good, with no missing resist areas or bridges.