How to 3D Print a Picture: Relief, Lithophane or Full Model

Route 2: A lithophane

In a lithophane, brightness becomes thickness, flipped, so dark areas are thick and block more light. It works for photos you will light from behind: a window hanger, a lamp shade, a night light.

Our free lithophane maker starts from thin, inverted settings: 0.8 mm at the thinnest and 3.2 mm at the thickest.

Prepare the photo for a lithophane:

• Tonal range matters more than resolution. A photo with detail in both the shadows and the highlights prints best.
• Crop to what you want. The tool uses the whole visible picture.
• Lighting in the photo becomes thickness. Harsh shadows print as thick, dark patches.

Set the thickness: a common starting point for white PLA is a minimum around 0.7 to 0.9 mm and a maximum around 2.8 to 3.1 mm, printed standing up. Your filament and your light decide the final values. Print a small test strip first. The full walk-through is in how to make a lithophane.

Route 3: A full 3D model

Here the picture is a reference, not a height map. Bake3D generates a textured 3D model from one image and fills in the sides the picture does not show. You can check it from seven views, then export an STL of its current pose from the Export tab. If the model is rigged, you can pose it first. This route uses credits. A free readiness check of your photo comes first, and packs start at $5 for 80 credits.

Prepare the picture for a full model:

• One subject on a plain background.
• A front or three-quarter view, with the whole body visible.
• Limbs, tails and wheels separated from the body. Hidden parts have to be guessed, so a clean outline matters more than megapixels.

Set the size on purpose: The size depends on how you make the STL. The studio’s STL keeps the model’s own numbers, and slicers read them as millimetres, so a character 1.8 units tall opens just 1.8 mm tall. Our free GLB to STL tool turns metres into millimetres instead, so the same character comes out 1,800 mm tall at scale 1. Either way, check the size in your slicer and scale it on purpose. The studio’s STL also uses Y as the up direction, so turn it upright in your slicer if it lies on its back.

For more on this route, see how to turn a 2D image into a 3D model and how to make a custom figurine from a photo. For a game piece at 28 or 32 mm, read how to make 3D printed miniatures.

All three routes use millimetres

Both of our free tools write STL files in millimetres, with a flat base at Z = 0. That is what slicers expect. Width sets the physical size, and the picture’s shape sets the other side. The tools sample the picture along its long edge, with a limit, so a 4,000-pixel photo does not turn into a file with millions of triangles.

STL files have no units inside them, which is why the size can surprise you. Our guide on 3MF vs STL explains why, and when 3MF is a better choice.

Check the STL before slicing

A successful download is not a promise that the print will work. Open the file in our free STL checker and read the report.

• A relief or lithophane should show one shell, watertight, with faces pointing the same way and a positive volume. Our tools build closed meshes, and automated tests confirm that.
• A full 3D model can have several shells if it has separate parts. But open edges, non-manifold edges or an inside-out result need fixing. Our free STL repair tool closes holes and turns flipped or inside-out faces. A modeling program handles the rest.

Then check what the checker cannot see: wall thickness for your nozzle or resin, overhangs, the best orientation and whether it fits your printer. Check the sliced layers too, not just the preview.

Know the limits

• A relief is a rectangle. Nothing in a height map can undercut. A ball in a photo becomes a dome, and a person becomes a raised outline.
• A lithophane reads light as thickness. Flash shadows and shiny spots print as shapes.
• A generated model guesses the hidden sides. Thin parts, touching limbs and unusual shapes are the usual trouble spots.
• The converters and the checker do not change the mesh. The STL repair tool fixes holes and flipped faces, but no tool here checks wall thickness or knows your printer.

The free tools run entirely in your browser, with no upload and no account. Pictures can be up to 32 MiB and 64 megapixels. The studio uploads your picture to make a model and uses credits. A job that fails refunds what it did not deliver, as the pricing page explains.