To capture detailed surface shape 3DSOM Pro can calculate a point cloud — a dense set of 3D points in space. This data is generated using pairs of photos that were taken close together (or optionally pairs taken with the 3DSOM Pro stripe pattern projected onto the object surface). The Point Cloud Wizard is used for this task.
If you are using projected stripes, for each rotation angle of the object, a digital projector should be used to illuminate the object with a pattern of horizontal stripes. You can use two or more cameras to capture the appearance from several elevation angles (see Using projected stripes). Alternatively, you can use a single camera placed at two elevation angles as long as the calibration target(s) is visible in all the shots. If you are moving a single camera, you can either use a computer controlled turntable to take a complete sequence at each elevation or move the camera for every object rotation angle.
The latest version 3DSOM Pro can now use pairs of photos taken from slightly different viewpoints to build a dense point cloud. For more detail on how to take these shots see Easy workflow 1 - Single camera walking around object and Easy workflow 2 - Single camera with tripod.
Adjust the "density" slider to vary the number of points that will be calculated. A high density cloud will require more processing power but result in more 3D points which can result in better accuracy. A multi-core fast processor is recommended for calculating a high density cloud.
The "Remove outliers when done" option should be selected to interactively eliminate erroneous outliers after generating the 3D points. If you already started from an existing approximate point cloud you should not need to select this option.
The "Restrict image pairs" parameters are used to determine which pairs of images are used if you are using projected stripe patterns. If you are using the naming convention in File Naming Convention you will use the "...using trailing digits" (default) option - which selects pairs of images with the same numerical suffix. If you don't have projected stripes then the default unchecked options should be used.
Click the button to start the process. The points will be displayed in the 3D view as they are calculated. You can rotate the scene using the viewpoint controls as normal.
Use thebutton to see the point cloud more clearly without the current mesh. Pairs of images are processed in turn and the resulting points displayed with a lighting effect to show the point orientation (normal direction).
When you are happy select the button.
To update the surface geometry using the generated point cloud you will now need to run the Surface Wizard. See Optimising the surface geometry.
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