The DJI P1 is a full-frame sensor camera with interchangeable lenses that produces incredible 2D and 3D models with survey grade accuracy. But in order to get the accuracy you need, you will have to perform a lens calibration when you first get the camera, or any time you swap lenses. The purpose of the calibration is to find the optical center of the lens. This is the point used for the GPS position data written to each image. Without the calibration, your data can be slightly shifted.
Calibrating the lens is simple using the following steps. You will have to plan an oblique mission and process the images using DJI Terra to get your calibration file. Keep scrolling for a detailed video tutorial.
Step 1 - Creating an Oblique Mission
It is recommended to find an area with varying elevation and structures so that you have contrast within you model. Create an oblique mission with at least 100 oblique photos (not including nadir photos). Execute the mission to collect the images needed for processing.
Step 2 - Reconstruction
Create a 3D reconstruction using DJI Terra. Keep the resolution at "high", the scene as "normal", and the computation method as "standard computation". Use "arbitrary coordinate system" in the advanced settings.
Step 3 - Get the Calibration File
Next you will need to export the processed reconstruction. You will only need the aerotriangulation result. Open the "AT" folder and then the "report" folder and you find a file named "sfm_report.json".
Step 4 - Upload File to P1 Camera
Once you've located the file, copy it onto a blank SD card and install the SD card in your P1 camera. Power on your aircraft with the P1 installed and the camera will calibrate automatically.
Remember, this process needs to be repeated any time you swap lenses on the P1. We hope this helps!