Engraving with the Endurance lasers and engravers is possible only at 300 dpi.
This limitation is due to:
Endurance is working at the selection of more powerful lenses to ensure engraving at a higher quality (resolution).
Learn more about Endurance Makeblock laser engraving / cutting machine
Learn more about Endurance DIY laser engraving / cutting device
Learn more about Endurance WanHao combo unit: 3D printer + laser engraver + laser cutter