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Engrave a photo with a laser

A laser burns or it does not, and a photograph has smooth tones in between. Software gets from one to the other in one of two ways: vary how hard each dot burns, or burn every dot at the same strength and let the number of dots carry the tone. The second is called dithering, it is what most photo engraving uses, and RapidCAM does both. This guide engraves a picture and shows you what each choice does.

Open RapidCAMNothing to install, no account.

  1. Describe the piece, as a laser job

    Choose New Project. Under Machine, set Machine type to Laser, and under Stock give the width and height of the piece you will engrave (100 mm square here).

  2. Drop the picture and tune it

    Drag a picture (PNG, JPEG, WebP, BMP or GIF) onto the RapidCAM window. First comes Adjust Image for Engraving, which says what the machine will do: dark means a deeper, stronger burn, and white is left untouched. Tune Brightness and Contrast until the subject reads clearly (the preview is what the machine reproduces), then press Place.

    The picture lands in the middle of your material, 80% of its shorter side (80 mm on a 100 mm piece), keeping its shape. You can set an exact size in the Properties panel.

    The picture lands on the blank, selected: 80 mm on a 100 mm piece.
    A shaded sphere picture placed in the middle of a 100 millimetre laser blank, selected

    One thing to know about light backgrounds: anything lighter than about 96% white is treated as something to engrave, and a pale grey backdrop will be covered in faint dots. If yours is grey rather than white, raise Brightness until it goes white and the dots disappear.

  3. Engrave it as dots

    With the picture selected, open the Toolpaths tab and press + Add Toolpath. Set Type to Engrave (centreline). The name says line, but the description below it is the one that matters here: it runs the beam along a line, or engraves a raster image by modulating power per dot. A picture is the second.

    The Laser section starts at feed 1000 mm/min, power 80%, one pass, and a Line interval of 0.10 mm, the distance between scan lines (start near your laser’s spot size). Then the choice that decides how the picture looks: Dithering.

    Engrave, with Dithering set to Floyd–Steinberg. The strip below it shows the dot pattern.
    The Add Toolpath dialog set to Engrave with the picture picked, the laser settings, Floyd–Steinberg dithering and a magnified dot pattern

    Off (greyscale power) makes darker mean a harder burn. Many diode lasers respond very unevenly to power, so mid-tones can come out muddy. The other four fire every dot at one strength, and tone becomes dot density. RapidCAM’s own advice on them: Floyd–Steinberg is the classic; Jarvis is smoother; Atkinson is higher contrast and good on wood; Ordered is a fast, regular pattern. Pick one and the Pattern strip shows it magnified, one pixel to a dot.

    The same picture through each dither, one pixel per dot. Drawn by RapidCAM's own dither code on a test picture, enlarged so each dot shows; a real burn also depends on your laser and material.
    The same shaded sphere shown as greyscale and then as dot patterns for Floyd–Steinberg, Atkinson, Jarvis and Ordered dithering

    Read the figure the way you would read the wood. Atkinson sends the lightest tones to bare material and the darkest to solid burn, which is why it looks cleaner and harder. Floyd–Steinberg and Jarvis keep the whole gradient. Ordered shows its grid. There is no best one: there is the one that suits this picture on this material, which is why you try them on scrap.

    Invert (engrave light areas) flips it for a material that gets lighter when it is engraved, such as dark anodised aluminium. Press Apply.

  4. Test on scrap first

    The laser Toolpaths panel has a Material Test button beside + Add Toolpath: it generates a power-against-speed test grid, so you can find the settings your laser and this material like instead of guessing. Run it on a scrap of the same material, pick the cell you prefer, and put that power and feed into the toolpath. Save as preset… in the dialog keeps a combination under a name for next time.

  5. Generate the G-code

    Press Generate G-code. The Export preview shows the job’s size and an estimated time (about 29 minutes here), checks the program, and has nothing to report when the picture sits on the material. Export saves the .nc file. The estimate is an optimistic one, because it assumes the machine always moves at full speed.

    The export preview for the 80 mm picture: about 29 minutes, nothing to report.
    The Export preview dialog for the engraving showing an estimated time and no pre-flight findings

    Laser jobs start on a GRBL post that uses M4, which lowers the power while the head slows for a corner. If your controller needs a different one, pick it in Settings (Machine Settings) before you export.

    Before you run it: focus the laser, frame the job to check it sits where you expect, wear eye protection rated for your laser, and stay with the machine while it runs.

  6. On a router instead

    A CNC cannot fire dots, but the picture can still be made: the 3-D Relief (image or model) toolpath carves it as a surface, and its V-carve halftone (photo as V-grooves) option reproduces tone with grooves whose width carries the shade, which is much faster than plunging a hole for every pixel.

Open RapidCAMBrowse designs

Checked against RapidCAM on 2026-10-05. If something here no longer matches what you see, the app has changed and this guide is behind: please tell us.