I am just getting started in metal etching and plan to use the sun as my exposure source. In reading about having to experiment with exposure times and using a Stouffer guide, I can't help to think one should be able to read the light intensity with a common photographic light meter and consistent results can be had. My uncle, an retired printer and lithographer, gave me a real nice meter that you can dial in the asa speed of your film and it tells you what exposure time to use on your camera. Anyone done this?