Should 3D Printed Lithophanes Be Positive or Negative?

Lithophanes are 3D printed pieces that are based on source photos. An artist can use several software tools to create them, and the positive/negative settings play a critical role in determining how the lithophane turns out.

The negative setting for 3D printing lithophanes is suitable for regular photos. The whiter areas of the source photo will be thinner in the lithophane to accurately project the image as light passes. The positive or negative toggle in the settings impacts how the dark and bright areas get treated. 

When it comes to personalized gifts — it doesn’t get much better than a 3D-printed lithophane of a unique photo. This article will walk you through the steps for creating a lithophane and which software settings you should have. Let’s get started.

How Do Lithophanes Work?

Though lithophanes have a rich history as an antique art form, it has taken all-new turns with the advent of modern 3D printing technologies. You might have seen them on display, but have you ever wondered how those intricately detailed pictures are formed?

Lithophanes work by using a light source behind them to project detailed photos. These pieces of porcelain or plastic have varying thickness levels in different areas to display an image. Thinner areas allow more light to pass through while thicker ones block it. 

Select the Right Source Picture for Lithophanes

A lot of complex work goes into creating 3D printing models for lithophanes — and it all starts with choosing the right picture. Not all photos work well as subjects for 3D printed lithophanes. 

Here are some considerations for selecting the right one for your next project:

• Choose a picture that doesn’t have unnecessary details. Ideally, the subject should be clearly visible with a simple background.
• You should only 3D print lithophanes of pictures that don’t rely on color. For instance, a scenery might owe most of its beauty to its natural colors — but lithophanes will only portray shades of gray. 
• Lithophanes produce images with differences in the brightness of shades. So, the higher the contrast ratio (difference between the lightest and darkest shade) of your source image, the clearer your lithophanes will turn out.

Choose the Right 3D Modeling Application

To generate a lithophane, you’ll first have to create a 3D model for it based on a source image using software tools. For that, you have several choices that have their pros and cons. Some are more professional but more complex, and some are easy-to-use yet limited.

Here are some options you can choose from:

• Ultimaker Cura Software
• Lithophane Maker
• 3dprocks
• Adobe Photoshop

The most popular software among the 3 is Ultimaker Cura. It’s one of the oldest software tools that many 3D professionals swear by. The app is easy to use, even for beginners looking to import source photos and convert them to 3D photo mesh. 

However, with simplicity comes a lack of customizable options — and it’s the same story with Cura. However, the tool certainly offers all essential settings in the interface. Experienced pros won’t feel too limited — unless it’s a highly complicated project. 

Other options include web-based online tools like Lithophane Maker or 3dprocks. They take care of the main part of creating 3D models for a lithophane: converting your source image to 3D mesh. 

If you’re looking for more freedom on the options and software features to tweak your projects down to the finest details, you might want to invest in some paid professional piece of software like Adobe Photoshop. With such software, you’ll have all the options you could need with a refined user interface. For instance, you’ll get to produce 3D printed lithophanes for shapes like cubes, spheres, etc. 

All of these software tools have their own strong and weak points. The right choice depends on your needs and preferences as a 3D artist, and a paid subscription falls into your budget.

Key Settings in 3D Lithophane Modeling Software

Cura has a drag & drop editor and key customization options like “light smoothing” and “darker is higher.” You’ll want to keep both of these enabled on most of your projects. The darker is higher features makes it so that, the darker patches of the source photo have a thicker print on the lithophane to block light and produce shadows. 

Even for other pieces of software, these settings for ‘positive/negative image’ are critical. It determines whether the brighter areas of your source image are thin or thick on the lithophane. Choose the negative setting to make darker areas thicker and whiter ones thinner. If you’d prefer the opposite for a particular project — go with the positive setting.

Most software tools for 3D modeling lithophanes allow you to tweak your image’s brightness, contrast, and shading. Simply open your source image in the app and use the sliders to adjust its contrast ratio and brightness. 

However, keep in mind that all settings in your software tool should depend on your personal preferences. Going with the defaults is your best bet if you’re not working on anything too technical and just need a regular lithophane.  

Some apps also offer a Binarize option for shadeless black and white lithophanes. When toggled on, your brightness, gamma, and contrast settings will be ignored. 

Note that there’s also a setting for max pixels proportion. Most lithophanes need no more than 500 pixels. The higher that number, the longer your slicing times get — and by a lot. If 500 pixels take an hour to slice, 1,000 pixels may go overnight.  

Finally, once you’re done optimizing the settings for your lithophane, upload your image and begin processing. 

Conclusion

Besides your choice of the source photo or software tool, the quality of your 3D printer also plays a primary role in determining how your lithophane turns out. Make sure it’s well-calibrated to print the perfect lithophane. At first, it’ll look nothing more than a scratchy piece of porcelain, but put it in front of a lamp and see the magic. All the best!