Setup Page

The Setup page is for setting up the following for 3D computation:

1. reference points,
2. constraints,
3. calibration points selection, and,
4. initial camera parameters.

The Setup page contains four subpages for selecting what to setup:

Reference Point subpage

The Reference Point subpage contains the two following command buttons:

• 'Open Point Info Window' button: invokes the Point Info window for setting reference points. Once a point is set as a reference point, the corresponding marks are highlighted in green.
• 'Clear all reference points' button: resets the reference points to invalid or computed and points are no longer highlighted.

Constraint subpage

The Constraint subpage contains the following elements for creating and editing constraints:

• Constraint type: this option menu is for selecting a constraint type which is one of: Collinear, Coplanar, Same X, Same Y, Same Z, Same XY, Same XZ, Same YZ.
• Name field: the name of the current constraint being edited. To create a new constraint, enter a name here and press Enter key. All points that belong to the current constraint are highlighted.
• Constraint listbox: it lists all the constraints of the current type.
• Weight field: this input field is for changing the weight of the current constraint. This step is optional and the default value can be used usually.
• Distance field: used for entering the distance in a distance constraint.
• Show button: invokes the computed constraint parameters dialog box which displays information about the current constraint.
• Delete button: deletes the current constraint.

Calib. point subpage

The 'Calib. point', or Calibration Points, subpage is used to select points to be used in computing camera parameters. When the "Selected Points" is checked in the "Calibration point" field in the 3D Computation dialog, the 3D computation will only involve the points selected in this subpage.

This step is optional. If no points are selected, Photo4D uses all marked points.

• Use this subpage if:
  1. a project contains many images and thousands of points, or;
  2. when some points cannot be marked accurately.
• Clear all calibration points: press this button if you want to select a new group of points.

Camera param. subpage

The Camera param., or Camera parameter, subpage is used to open the Camera Parameter window. There is no need to know the exact location and direction of cameras when taking pictures. Using an iterative algorithm, Photo4D is able to compute these and other camera parameters automatically. However, Photo4D needs some rough initial values in order to start computing.