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Point cloud and digitizing

Hello,

I wonder if the arbitrary choosen point size in the 3D-viewer affects in any way the digitizing accuracy.

My impression is that the sole role of the point cloud is to connect surface positions to corresponding images. It seems that is possible to adjust the position of a marker or a vertex in the right panel of the screen by very tiny increments, probably limited only by the size of pixels in the original images.

Am I correct ?

regards
Tibor

Hi Tibor,

The Point Size changes the display size of the points in the 3D view. It does not affect the accuracy of the digitization as the same points are displayed in different sizes.
However, if you select a small Point size, for example, close to 1, then some points might not be displayed when viewing the point cloud from far away.

The following options are available for adjusting the position of existing geometry:

  1. Editing geometry in the 3D view - Drag and vertex to the new position. Keep in mind that the vertex can only be moved to an existing point in the point cloud. The accuracy depends on the resolution of points and the quality of the point cloud.

  2. Editing geometry on images - Click on the vertex on the image and drag it to the new position on at least two images. The position of the vertex is automatically changed and updated based on where you place the markers. The accuracy depends on how accurately you place the markers.

  3. Editing geometry with vertex editor - Type the coordinates of points or adjust the coordinate values with the +/- button. It is updated with any value you specify.

Best,

Hello and thanks for the answer !

About the second option:
Is there an interpolation used between points in the cloud guided by the position derived from the images ?

When adjusting the position of the vertex on images only the position of marks are taken into account. There is no interpolation between the original position of the point in the 3D view and the position determined based on the marks.