How accurate are the volume measurements? What is the error of margin on it?
The relative horizontal accuracy is <1% and the relative vertical accuracy is about 2%. These are the relative accuracies. The absolute accuracy depends on the quality of the GPS receiver and the quality of the signal at the time of capture.
The volume measurements have been proven to be <1% as well.
iniciar sessão para comentar.
I'm testing the accuracy of the Phantom 3 Professional to make one orthomosaic. I used 7 ground point controls in my model. Using the measuring tool I get accurate results for small distances. When do longer distances measures I have accumulative error. Can help me fix these results?
Georeferencing done using GCPs can easily have more error over large areas if the GCPs are not done well. The errors will be less around the areas of the GCPs but the outlying areas have less info to work with to be accurate. Overall, the Camera GPS workflow will be more accurate in general, especially over large areas. Since you are using a P3 Pro you are likely best off using the standard workflow for your jobs if making accurate relative measurements is your goal.
Email us with some screeshots of specific examples and we can help you try to work through them.
Okay Ryan, I'll check the ground control points accuracy and prepare an email with some screenshots. Is there any possibility of these errors are generated by a P3 Pro camera image distortion? Thanks a lot for the help.
Lens distortion is taken care of in the processing and shouldn't be an issue in the output. As long as the output looks OK and isn't wildly distorted the measurements values should be pretty good.
