A diode laser darkens wood and lightens slate, one dot at a time. A photo needs the right tone for the material and the right DPI first; your laser software then makes the dots. DTO Studio (early access) prepares the picture; this is what it does and why.
Light wood (basswood, maple, birch)
- 254 to 318 DPI: the dots should just touch on your wood. Even, light grain gives the cleanest faces.
- Wood darkens fast, so the photo's middle tones are lightened before the dots are made, or faces turn to mud.
- Dots in the Jarvis or Stucki pattern (fine, smooth dots) read best on wood: pick it in your laser software, at the file's DPI.
- Low air assist keeps the scorch down. Wood can flare up: stay with the laser.
Slate
- The laser makes slate lighter, so the photo is inverted first: the bright parts of the picture are what gets marked.
- Contrast is pushed hard: slate's mark is a pale grey with few in-between tones.
- Low air assist (strong air blows the dust back), and the slate must be dry.
- Wipe it with mineral oil afterwards: the dark stone deepens and the picture pops.
Power and speed: test first
Published diode tables give a starting point by wattage for wood (for example the xTool D1 Pro and Creality Falcon tables); for slate on a diode the community reports disagree and we found no maker's table. Either way, burn a small power and speed test grid on a scrap of the same material before the real piece.
Diode wattage is the optical (output) power, not the electrical power on the box. A 10 W diode and a 40 W diode need very different settings.
The file
- A greyscale PNG of your edited picture with the DPI written into the file, so your laser software opens it at the real size. Let the software make the dots there: Jarvis or Stucki, at the file's DPI.
- A Pre-dithered (1-bit) PNG with Studio's own dots is optional; it is already dotted, so don't dither it again.
- Keep the size you picked: scaling the image in the laser software moves the dots off the spacing they were made for.