This scanning method is more convenient than scanning without markers. In this mode the object or supporting surface is covered with special round marks (markers).

In addition to construction of the object surface, in this mode the scanner finds marks, determines size and calculates their coordinates. If each of the following scans has enough related marks from previous ones, new fragment automatically will be placed in the desired position. In this way, all the pieces will automatically form a three-dimensional object model, making it easier for further processing of the scan data, speeding up the process of obtaining a 3D model.

Found marks form a reference grid. You can create a reference grid of markers in advance, and then scan the object. Thus each scan will be connected to the reference grid, and not to the previous scan, without the need for overlap between them.

From this it should be noted that you can stick fewer markers to an object. Reference grid can be used repeatedly, if you're using auxiliary object for your scanning process (for example, plate with markers). Reference grid can be uploaded in different formats: basegrid, obс, txt, dxf from third-party sources, for example, from photogrammetric system, that allows you to scan large objects (for example, vehicles) without significant loss in accuracy.

The dxf format is designed to provide faster data transfer when interacting between Agisoft Metashape Pro and ScanCenter NG.

When sticking markers to an object it is desirable to choose flat areas. In this case, on obtained model you can cut the section with the mark, and cover the blank space without significant losses in a result. Using a dark surface, which is "invisible" for the scanner, simplifies removing extra fragments when processing the model. An example of auxiliary surface - plate with markers

<aside> <img src="https://s3-us-west-2.amazonaws.com/secure.notion-static.com/ad7d8b8d-b7df-47b6-8951-d0bbc608ccf3/blank.png" alt="https://s3-us-west-2.amazonaws.com/secure.notion-static.com/ad7d8b8d-b7df-47b6-8951-d0bbc608ccf3/blank.png" width="40px" /> Markers should be attached as chaotic as possible. Avoid expressed patterns or curves, as this may provoke incorrect detection of markers. When using auxiliary surface, object should not move in relation to the markers during the scan!

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Marker type and size can be chosen at project creation. It is possible to automatically detect visible marker type and size in Markers menu.

Scanning procedure:

1. Stick markers on the object or auxiliary surface.

2. Prepare the object to be scanned (if needed). Create a new project with markers or open an existing one.

3. If the reference grid of 3D-markers is already created - load it through Markers → Load base grid function.

4. Using the Cross mode determine the correct distance to object.

5. Adjust exposure using the slider.

6. If you are creating a reference grid, сheck the Markers only box in the Scanning menu.

7. Start scanning.

8. Place the object/scanner to the following position and then start the scanning process. Do not change the position of the object regarding the marks! In order to view all scans, click on the title of the project.