Accurate marking is a key step for successfully computing 3D information. If a point on an object is marked as different points in separate images, this point is mis-marked. A mis-marked point not only results in wrong (x,y,z) coordinates for this point, but may also confuse Photo4D's 3D computation algorithm. This could lead to large errors for all the other points or even a computation failure. Therefore, it is very important to ensure that all the points are marked correctly and consistently in all images.
To check whether a point is marked correctly, select the point as the current point by clicking the left mouse button on one of its marks. By doing so, all the marks of this point in different images are highlighted in purple (default color). By examining the highlighted marks in all images, users can then determine whether or not this point is mis-marked.
The mark traversal feature (see Traverse Mark) provides a way to check many marks effectively.
In addition, the accuracy of mark locations determines the accuracy of 3D computation. The commands in the Image Menu can be used to zoom in or out of images to examine and modify mark locations
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