When I use alcohol (not acetone) with quality buds, then I will shake the shit out of it, by the end it will be very dark green, add the powdered activated charcoal, yes it's fine, but not so fine that normal filter paper won't remove it and you are left with a very very pale yellow, that dries to the finest quality honey oil. Yes there are no terpenes.
These day I only either do acetone and leaves with a quick rinse and no charcoal filtering, it's not worth the bother. But my go to extraction is simply the Slug33 fat mac, which naturally does preserve all the terpenes. I like the Slug because it's fun to use and I don't have to use bags to hold the weed, just stuff it in and squeeze it out.
I learned about activated charcoal in the 70's from people who use to make hash oil in Kandaha and import it into London. They cleaned it up with activated charcoal for personal use.
@madvillian420, I only use acetone for cleaning my glassware, it's much more efficient than iso, or on low quality trim. It's a much underused solvent. In the 60's because I didn't smoke tobacco we would dissolve oil in acetone and pour it over mint tea and dry it. It evaporates with no residue.