How to Turn an Image into a Laser Cut File
To turn an image into a laser cut file, start with a high-contrast picture, trace it to vector paths (Path > Trace Bitmap in Inkscape or Trace Image in LightBurn), clean up stray specks, make sure shapes are closed, set the real size in millimetres and save as SVG. Photos are engraved as raster images instead.
Your kid draws a dinosaur on the back of a receipt. You photograph it, drag the picture into the laser software, press Start, and the machine engraves a square block of brown mush with a faint dinosaur ghost in it. Welcome to the first rule of this topic: a picture is not a cut file. A laser cut file is a set of lines. Turning an image into one is called tracing, and when it works it feels like magic.
This guide covers both roads: tracing artwork into cut lines, and engraving a photo as a raster.
Pick the right road: trace or engrave
| Goal | Image type | Method | Result |
|---|---|---|---|
| Cut out a shape | Logo, silhouette, drawing | Trace to vector | Cut lines in SVG |
| Engrave a logo | Black on white artwork | Trace or use as image | Crisp fill |
| Engrave a photo | Portrait, landscape | Raster engrave with dithering | Dotted shading |
| Stencil | Bold shape with bridges | Trace, then add bridges | Cut-out stencil |
If you need lines to cut around, trace. If you need shades, engrave the image as a raster and do not trace at all.
Step 1: Choose or prepare the source image
Good sources for tracing share the same traits: strong contrast, clean edges, few colours. A black silhouette on white is perfect. A blurry phone photo of a pencil sketch is not.
Prepare it before you trace:
- Crop to the subject.
- Raise contrast. Open any editor and push the black point up until the background is pure white.
- Make it large. 1,500–3,000 pixels on the long side gives smooth curves.
- Remove everything you do not want to cut: shadows, paper texture, handwriting in the corner.
Pro tip: photograph drawings under a window, not under a lamp. A lamp casts a shadow gradient that the tracer turns into messy blobs.
Mind the copyright. Tracing a logo or a character you do not own and selling the result is a legal problem, not a technical one. Our own library is CC0, so you can learn from files like the seahorse ornament without worry; see the license.
Step 2: Trace in Inkscape
- Import the image (File > Import) and keep it linked or embedded.
- Select it and open Path > Trace Bitmap (Shift+Alt+B).
- Choose Brightness cutoff for a simple two-colour result.
- Set the threshold. Start at 0.45–0.55 and watch the preview.
- Under Options, set Suppress speckles to 2–5 pixels and Smooth corners to about 1.0. Tick Optimize paths.
- Press Apply. A black vector appears on top of your picture. Move it aside and delete the original image.
- Zoom in. If curves look lumpy, undo and increase the source resolution or lower the threshold.
Step 3: Trace in LightBurn
Import the picture, select it, and open Tools > Trace Image (Alt+T). Use the same logic: set Threshold, Cutoff, Ignore less than (to drop specks) and Smoothness. The preview shows the result live. Click OK and delete the original bitmap. If you want to engrave rather than cut, you can leave the bitmap in and use Image mode with dithering instead.
Step 4: Clean the paths
A raw trace is never ready. Run this clean-up list:
| Check | Why it matters | How to fix |
|---|---|---|
| Tiny specks | They cut as little useless holes | Delete, or set a higher speckle filter |
| Too many nodes | Jerky motion, wobbly lines | Path > Simplify (Ctrl+L) in Inkscape |
| Open shapes | Parts do not drop out | See fixing open contours |
| Floating islands | Centres of A, O, R fall out after cutting | Add bridges to make a stencil |
| Thin neck under 2 mm | Snaps in 3 mm plywood | Thicken in the drawing |
Common mistake: tracing a thin, hand-drawn line and cutting it as a single stroke. A line has no inside, so tracing produces a thin outline around the line and a laser cut then separates a spaghetti-thin shape that crumbles. Either thicken the line in the drawing to 2–3 mm or engrave it instead.
Step 5: Add structure, set size, assign layers
Decide what is cut and what is engraved. A traced silhouette usually becomes the CUT outline in red with a hairline stroke, and traced interior detail becomes a black ENGRAVE fill. Then set the real size. Select the group and type the width in millimetres with the aspect ratio locked. The lock is critical: a traced shape squashed to a different ratio looks odd and cannot be fixed later. If you are unsure how scaling affects holes and cut length, read how to scale laser files.
Save as Plain SVG, then check the file with the steps in how to prepare an SVG for laser cutting.
Engraving a photo instead
When the picture should stay a picture, skip tracing. Import the image, set it to Image mode, and choose a dithering method. These are typical starting values on plywood:
| Setting | Typical value | Note |
|---|---|---|
| Resolution | 254 DPI (line interval 0.1 mm) | 318 DPI for fine detail on CO2 |
| Dither | Jarvis, Stucki or Atkinson | Test; Atkinson is crisp, Jarvis smoother |
| Brightness | +10 to +20 | Wood darkens a lot |
| Contrast | +10 to +30 | Helps skin tones separate |
| Speed (diode 10 W) | 150–250 mm/s | Scan speed |
| Speed (40 W CO2) | 200–350 mm/s | Low power, 10–25% |
Photos engrave best on light, even wood with little grain. Dense grain adds its own lines to the image. See what DPI to use for laser engraving for the detail.
Troubleshooting
| Symptom | Cause | Fix |
|---|---|---|
| Trace is a solid black blob | Threshold too high | Lower the threshold |
| Trace is all outlines of speckle | Source has noise | Raise speckle filter, blur source slightly |
| Shape is stretched | Aspect ratio unlocked | Undo, lock proportions |
| Cut file has many separate islands | Letters and holes not bridged | Add 1.5–2 mm bridges |
| Edges look jaggy | Source resolution too low | Use a bigger source image |
Which tool for which job
| Tool | Cost | Strength | Weakness |
|---|---|---|---|
| Inkscape Trace Bitmap | Free | Good control, easy cleanup | Takes a few extra clicks |
| LightBurn Trace Image | Part of LightBurn | Fast, live preview, same program | Fewer editing tools |
| Illustrator Image Trace | Subscription | Strong colour tracing | Needs care with 72 dpi sizes |
| Online converters | Free or paid | Quick | Often jagged, copyright unclear |
For laser work we suggest tracing in Inkscape when the picture needs cleaning, and in LightBurn when it is already neat. In both cases, treat the result as a first draft. A good trace has smooth curves and few nodes: zoom to 800 percent and look at an edge. If you see a staircase, the source image was too small. If you see hundreds of tiny nodes along a straight edge, run Simplify.
Next step
Take one simple black silhouette, trace it using the settings above, size it to about 90 mm and cut it from a scrap of 3 mm plywood. When it comes out right, you have a repeatable path from drawing to ornament. For ideas on finished designs, browse the animal ornaments.
Questions and answers
Can I laser cut a JPG or PNG directly?
No. A laser cuts along vector paths. A JPG or PNG must be traced into paths first, or engraved as a raster image with dithering.
What is the best image for tracing?
A high-contrast black-and-white image at 1,500 pixels or more on the long side, with clean edges and no shadows or paper texture.
Is Inkscape or LightBurn better for tracing?
Both use similar controls. Inkscape is free and gives more cleanup tools; LightBurn is quicker if the image is already clean and you are staying in one program.
Why do the centres of my letters fall out?
Letters like O, A and R have islands. Once cut, the island drops out. Use stencil fonts or add small bridges of 1.5 to 2 mm if you want to keep them.
Can I engrave a photo on plywood?
Yes. Import it as an image, use a dithering mode, and a line interval of about 0.1 mm. Test brightness and contrast on scrap, because wood darkens a lot.