Lithophane
Generates a lithophane from a photo: a relief where dark areas print thick and light areas thin, visible against light. Flat or curved, with a backlit preview.
Generates a lithophane from a photo: a relief where dark areas print thick and light areas thin, visible against light. Flat or curved, with a backlit preview.
Portraits and photos with good contrast work best. The image is processed locally.
Min and max thickness in mm, size, frame, and flat or curved shape — with a backlit preview.
White or natural filament, 100% infill, 0.1–0.15 mm layers, and put a light behind it.
Between 0.6 and 0.8 mm in the lightest areas and between 2.5 and 3.5 mm in the darkest is the range that works best with white PLA, and it is where the ilove3d lithophane generator's defaults sit. The logic is direct: thickness blocks light, so the minimum sets how much light passes through the bright areas and the maximum sets how dark the shadows go. Dropping the minimum below 0.6 mm buys contrast but leaves fragile regions that crack when you lift the piece off the bed. Raising the maximum past 3.5 mm barely darkens anything further, because very little light gets through at that thickness anyway, and it costs print time and material. If you use a filament other than white, adjust downward: coloured materials need less thickness to block the same amount of light.
White or natural PLA, 100% infill, a layer height of 0.1 to 0.15 mm, and the piece printed on edge, standing on its long side. Each of those four has a reason. White PLA diffuses light evenly, whereas a colour tints it and a translucent material lets too much through. Full infill stops the infill pattern from drawing itself across the image when you hold it to the light. The fine layer height defines the gradient between tones. And the vertical orientation is the most important of the four: printed lying flat, the layer lines cross the image as horizontal stripes and ruin it; standing on edge, the layers run along the same direction as the relief and disappear. It is a slow print, several hours, but every one of those choices shows. A brim helps as well, because a piece standing on a narrow edge has very little contact with the bed and can tip partway through a print that long.
In a lithophane the material blocks light, so the relationship runs opposite to intuition: the DARK areas of the photo need MORE thickness in order to block more light, and the light areas need less. The ilove3d lithophane generator already performs that inversion for you while building the geometry, so loading an ordinary photo gives a correct result with nothing to adjust. If it looks inverted — dark faces where they should be light — the most likely cause is that the manual invert control is switched on, which exists for images that already arrive as a negative. The other common cause is looking at the piece with no light behind it: under front lighting, a lithophane always looks the reverse of how it will look backlit. Checking it against a window or a phone torch before committing to the print takes seconds and settles the question without wasting hours of filament.
Portraits with even lighting and good contrast work best, and that is not a coincidence: a lithophane has a considerably shorter tonal range than a screen, so it translates images whose information already sits in the midtones far better. Very dark photos lose everything in the shadows, because the maximum thickness cannot distinguish one black from another. Busy backgrounds confuse the eye, because subject and background both end up rendered in grey. And extremely fine detail — loose strands of hair, small text, a railing in the distance — falls below what the nozzle can reproduce at all. The backlit preview in the ilove3d lithophane generator exists so you can see all of that before committing to a four-hour print. Cropping tightly around the subject before uploading usually helps more than any setting, because it spends the tonal range on the face instead of on the background.