The acquisition and calibration of metric frames is also very simple: just open the stack "Photogrammetry" , existing in the "archive" folder, and select the " New Tab. " A series of dialog boxes ask for the data necessary for the acquisition and use of the pair of metric frames. At the end of the operation, the program shows the four reference brands, on which the user must simply click. The data is stored in a series of fields contained in a part of the card, kept hidden. By selecting the "Catalog" button, a scrolling field containing the list of all the frames is displayed at the bottom of the tab itself . With a "click" on the name you switch to the corresponding "card". Other buttons allow you to:

• search through the dialog, based on any data;
• order the cards according to any personal data;
• repeat the calibration operations or close the stack.

As you can see in the figure, each card also shows, in reduced dimensions, the frame taken from the left camera. By selecting the "update" button from the "photogrammetry" card, the program opens the stack of the same name, in minimum dimensions, and by browsing all the pages it transfers the data of each card to the scrolling field, called "photogrammetric archive". Finally, it should be noted that when each tab is opened, the program searches for the guide frame in the archive folder: it is obvious, therefore, that if the stack is taken out of this folder it will no longer be able to show the images.