Laser engrave wood w or wo finish?

[Chris Barnett]

Need engraving done on wood plaques. Should wood be left plain or finished (varnish, poly, shellac etc) before having laser engraving done? I have no idea who would do the engraving and have no information on what machine would be used for the engraving.

[Chuck Stone]

Some prefer a finish on the wood. It makes cleaning any residue easier and depending
on the finish used, makes it less likely that any color fill will bleed.. giving you
a sharper image. But some prefer to work on unfinished wood, using spray paint
as fill and then sanding the surface afterwards. Each has it's own merits; seems to
depend on the project materials and the shop you use.