Illinois Drone Photography and Mapping

So, speaking in terms of vertical accuracy, does drone mapping using photogrammetry become more accurate when flying the drone closer to the ground surface?

In general, flying a drone closer to the ground surface can potentially improve the vertical accuracy of drone mapping using photogrammetry. The accuracy of photogrammetry relies on capturing high-quality images from different angles to create a 3D model or map. By flying the drone closer to the ground, you can increase the image resolution and capture more detail, which can enhance the accuracy of the resulting map.

When a drone is flown at a higher altitude, the ground sampling distance (GSD) increases. GSD refers to the distance on the ground that each pixel in the image represents. A higher GSD means that each pixel covers a larger area, resulting in lower detail and potentially reduced accuracy.

By flying the drone closer to the ground, you can decrease the GSD, which allows for capturing finer details and potentially increasing the accuracy of the generated map. This is especially important when mapping objects or features that require higher resolution, such as small structures, intricate terrain, or objects with precise dimensions.

However, it’s worth noting that the relationship between flying height and accuracy is not linear. There is an optimal flying height that depends on various factors, including the drone’s camera specifications, the desired level of detail, the terrain, and the specific photogrammetry software used. Flying too close to the ground may result in incomplete coverage or excessive overlap, which can lead to issues in the reconstruction process and reduce accuracy.

Therefore, it’s essential to consider the specific requirements of your mapping project and consult the documentation or guidelines provided by the drone manufacturer and photogrammetry software to determine the ideal flying height for achieving the desired level of vertical accuracy.