Production and Calibration of a Lambertian Surface Based on Barium Sulfate (BaSO4) for the Calibration of Multispectral Cameras

Drones, or unmanned aerial vehicles (UAVs), are increasingly utilized across diverse fields such as agriculture, environmental analysis, and engineering due to their ability to capture high-quality multispectral imagery. To ensure the accuracy of these images, radiometric calibration of onboard multispectral cameras is essential. This study aimed to develop and calibrate a low-cost Lambertian surface using barium sulfate (BaSO4) for radiometric calibration of UAV-mounted multispectral cameras. A stainless steel mold was designed to compact BaSO4, and the resulting surface was calibrated using an ASD FieldSpec HandHeld UV/NIR spectroradiometer and a Spectralon plate as the reference standard. Results showed a strong correlation (Pearson’s r = 0.9988) between the BaSO4 surface and the Spectralon plate, confirming that the BaSO4-based surface is a cost-effective alternative for producing diffuse Lambertian surfaces with performance comparable to the standard.