LaserCanvas
Engraving photographs on wood
A laser has one power level per dot, not a grey scale, so a photo must be dithered into dots before it will read as tone. Prepare the image with high contrast and a light crop, use a pale even-grained wood like maple or birch, and keep the line interval fine — around 0.08 to 0.1 mm.
The laser cannot do grey
At any instant the beam is on or off at a given power. It cannot make a pixel "40% dark" in the way a printer’s ink can. Shades have to be built from density of dots — more burned dots per area reads as darker. Converting a continuous-tone photo into that pattern is dithering.
Send an undithered greyscale image and the software will do something on your behalf — usually threshold it, which throws away every midtone and gives a harsh black-and-white blob. That is the single most common reason a photo engrave looks like mud.
| Dither | Looks like | Best for |
|---|---|---|
| Floyd–Steinberg | Fine scattered grain | Portraits and photos generally — the usual default |
| Jarvis | Softer, more diffuse | Smooth gradients such as skies and skin |
| Stucki | Sharper than Jarvis | Detailed images with fine texture |
| Ordered / Bayer | Visible cross-hatch pattern | A deliberate retro look, not realism |
| Threshold | Pure black and white | Line art and logos — never photos |
Prepare the image before it reaches the laser
- Crop tight. Engraving is slow; every millimetre of background costs time and adds nothing.
- Convert to greyscale and judge it there. If it does not read in grey, it will not read burned into wood.
- Raise contrast, hard. Wood has less dynamic range than a screen. Push blacks and whites further apart than looks right.
- Brighten slightly. Wood darkens as it burns, so an image that looks correct on screen comes out too dark.
- Sharpen. Dithering softens detail; a little unsharp mask beforehand compensates.
- Resize to final size at around 300 dpi. Engraving a 200 dpi image at twice its size just enlarges the dots.
Wood choice matters more than settings
| Wood | Result |
|---|---|
| Maple, birch, basswood | Pale, even, minimal grain — the best contrast and the usual choice |
| Alder, cherry | Good, slightly warmer tone |
| Plywood | Works, but the surface veneer is thin — a deep engrave goes through it into the glue |
| Oak, ash | Strong open grain competes with the image |
| Pine | Poor — resinous, and hard and soft bands burn at different rates |
The principle: the laser darkens the wood, so anything the wood is already doing — grain, knots, colour variation — is noise added to your image. Pale and featureless wins.
Settings
- Line interval 0.08–0.1 mm. Coarser and the scan lines show as banding.
- Low power, high speed. You are darkening the surface, not removing material. Too much power and the dots merge into a solid burn and the midtones vanish.
- Engrave across the grain where you can — an even tone is easier to achieve perpendicular to the grain than along it.
- One pass. A second pass lands slightly differently and blotches the tone.
Finishing
- Mask the surface with transfer tape before engraving. The tape takes the smoke stain; peel it and the unengraved wood is clean.
- If unmasked, wipe with a barely damp cloth afterwards to lift surface soot. Do not soak it — the burned areas will smear.
- A matt clear finish deepens the contrast noticeably. Test on a scrap first; some finishes yellow the pale areas.
Common questions
Why does my engraved photo look like a dark blob?
Almost always missing or wrong dithering, plus too much power. Without dithering the midtones are thresholded away, and with too much power the dots merge into solid burn. Dither with Floyd–Steinberg, raise the image contrast, and drop the power until midtones survive.
What is the best wood for engraving photos?
Maple, birch or basswood — pale, even and with little visible grain. The laser darkens the wood, so any grain pattern competes with the image. Avoid oak and pine, and be careful with plywood: the face veneer is thin and a deep engrave can burn through into the glue line.
What line interval should I use for photos?
Around 0.08 to 0.1 mm. Coarser and the individual scan lines show as banding across the image. Finer takes longer without visible improvement on wood, because the material cannot hold detail below roughly that scale anyway.
Should I engrave a photo in more than one pass?
No. Each pass lands fractionally differently, so a second pass blotches the tone rather than deepening it evenly. If the result is too faint, slow down or raise power slightly on a single pass instead.