March 19, 2020
Both, new and professional users alike, sometimes face challenges scanning certain objects. The problem, most often, becomes evident when the scanner seems to be unable to "see" the given object in its field of view. Despite, otherwise, working properly and being perfectly capable of scanning other objects. A problem like this might be caused by a difficult surface.
What is causing the problem?
For the purpose of this article, a difficult surface includes any surface that the scanner is unable to reconstruct (or "see") due to the particular physical properties of the surface material.
Which surfaces are challenging?
For optical scanners it could be a challenge to scan dark (black), reflective, transparent, translucent materials, or surfaces without a solid structure, such as fur, hair, etc.
What's going on?
In order to reconstruct an object's shape in 3D, an optical scanner projects a structured light pattern onto the object's surface and captures the light's reflection evaluating the pattern deviation and, thereby, calculating the object's shape. This process works flawlessly on most type of surfaces, except those made of materials which do not reflect light in the ordinary fashion. Below are a few examples:
| Material type | Problem | Typical examples |
| Black-colored | absorb some of the structured light pattern | potentially, any black materials |
| Red-colored | Only applicable to Spider and Micro scanners, this color does not work best with its blue LED 3D Flash | some types of red surfaces, especially the ones fitting into one or more of the other groups in this table |
| Reflective | reflect too much | mirrors, metals, galvanized, polished surfaces |
| Transparent | do not reflect, pass the light through | glass, ice, water and other liquids |
| Translucent | diffuse the light | candle wax, certain 3D printing filament, some types of stone |
| No solid structure | reflect the light, but the scanner is unable to properly calculate the object's shape | hair, fur, down, dry cotton, some meshed surfaces |
The above list is not exclusive and some difficult surfaces might fit into several categories, such as a black polished leather shoes, which are both black-colored and reflective.
What to do?
If you encounter a difficult surface, use the following tips to help you scan it with good quality results:
- Use a scanning spray or another suitable coating for the surface.
- Increase the scanner's sensitivity.
- for Artec Eva scanner, the sensitivity is adjusted automatically
- for Artec Spider/Space Spider, use the applicable slider in the main scan panel "Advanced" settings.
- Adjust scanning angle and distance. This simple step can really make a great difference. Certain surfaces can be "seen" by the scanner when viewed from a specific angle and distance. Therefore, please attempt to alter your scanning distance and angle to find the combination where the surface will be scanned best. Depending upon the object's size and shape, you might be able to carefully scan it this way.
Our team is here to help! If you have any questions or issues, please do not hesitate to contact us by emailing support@artec3d.com or by clicking on "Submit a request" button at the bottom right side of the screen. We will always be happy to assist you and will get back to you as soon as we can.