To manually calibrate the project images with the radiometric calibration target information, follow the instruction described below:ġ. DSM, Orthomosaic and Index > Index Calculator. The reflectance values can still be reviewed in the processing options: Menu Process > Processing Options. To calibrate the project, simply import the calibration target images along with the other images during the project creation: Step 2. In possession of both radiometric calibration target and camera supporting automatic importation and marking (for more information: Radiometric calibration target), the pictures of the target are automatically recognized by the software and the target region and appropriate reflectance values are saved in the project. How to use calibration target images in Pix4Dmapper? If this is not the case, it is recommended to take the image from the ground. If a target is big enough to be properly visible from the air, then the image can be taken from the air. The radiometric calibration target should cover enough pixels to get good statistics. Should the radiometric calibration images be taken from the ground or while flying? During the flight: The target should be big enough to be properly visible for the UAV and cover many pixels on the capture.It is important that the weather and lighting conditions are as similar as possible to the ones during the flight. Before or after flying: It does not matter if it is taken before or after flying.The radiometric calibration image can be taken immediately before or after each flight or during the flight: Should the radiometric calibration images be taken before or after flying? Check the calibration target shots while on the field to assess the quality of the images and avoid under/overexposure.It helps in case of overexposure: Radiometric calibration target. Take several captures of the calibration to ensure to get at least one valid calibration image.Ensure that the camera GPS writes correctly the time and location information for the processing of the calibration images.If the images are taken from the ground the camera holder should stand around 1 meter away from the target and not be facing the sun.We recommend placing the target on top of a fairly reflective surface for the auto exposure not to overexpose (e.g.
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