diff --git a/source/images/rotation.gif b/source/images/rotation.gif new file mode 100644 index 000000000..abbc38e89 Binary files /dev/null and b/source/images/rotation.gif differ diff --git a/source/tutorials.rst b/source/tutorials.rst index b6e242c38..676425088 100644 --- a/source/tutorials.rst +++ b/source/tutorials.rst @@ -41,6 +41,15 @@ To mitigate this effect, there are a few options but the simplest are as follows As this approach to flying can be take longer than typical flights, a pilot or team can fly a small area using the above approach. OpenDroneMap will generate a calibration file called cameras.json that then can be imported to be used to calibrate another flight that is more efficiently flown. +Alternatively, the following experimental method can be applied: fly with much lower overlap, but two *crossgrid* flights (sometimes called crosshatch) separated by 20° with a 5° forward facing camera. + +* To get good 3D results, you will require 83% equivalent overlap and sidelap, which for a pair of crossgrids using 68% overlap and sidelap will achieve this. +* To get good 2D and 2.5D (digital elevation model) results, you will need 42% overlap and sidelap for an equivalent 70% overlap and sidelap. + +.. figure:: images/rotation.gif + :alt: animation showing experimental optimum + :align: center + Vertically separated flight lines also improve accuracy, but less so than a camera that is forward facing by 5°. .. figure:: images/forward_facing.png