This chapter explains how to use coded targets in 3DF Zephyr in order to further improve the cameras orientation phase.


3DF Zephyr’s coded targets are square-shaped (see image below).



In order to print coded targets just click the Tools button in Zephyr’s menu bar and then on Control points > Print Markers. You can print as many targets as needed.


3DF Zephyr supports 16 bit coded targets: their size strictly depends on the kind of 3D reconstruction and the related photographic survey as well.


Recommended settings are as follows:


Close Range and Human Body                4 targets per sheet (A4 size)

Urban                                                2 targets per sheet (A4 size)

Aerial                                                1 target per sheet (A4 or A3 size)


You can define the amount of targets per sheet by editing the printing menu settings on Windows (the term “page” implies a target inside that menu).

It is recommended NOT to use coded targets randomly; instead it is highly recommended to use them in their own numerical sequence (1, 2, 3, 4, etc. and not 4, 13, 22, etc.).


With 3DF Zephyr, you can also automatically detect standard targets, either square, round, or custom ones.

When a photographic survey is completed and after the cameras orientation phase is done you can start the automatic detection of coded targets by clicking on Tools > Control Points > Detect Markers.

In the new window you have to specify:


  • The markers family: allows to choose which markers have been used in field.
  • The subsampling;
  • The gaussian blur intensity;
  • The number of coded targets within the scene.


After clicking the confirmation button, 3DF Zephyr will start the automatic target recognition and will set the control points based on the detected targets.


NB: Please note that the automatic target recognition has to be started AFTER having completed the camera orientation phase in Zephyr.