The status of aerial photogrammetry in South Africa: a transition to digital imagery system

Abstract

The digital image camera technology has revolutionized the aerial imagery capture throughout the world. It has provided high spatial and spectral resolution together with superior efficiency and reliability compared to the traditional analogue aerial imagery method. In so doing, this has provided great accuracy in various photogrammetric applications. The South African survey and mapping organisation currently known as Chief Directorate: National Geospatial Information (CD: NGI) has been capturing aerial photography dating back as early as the 1930s. However, from 2008 CD: NGI embraced a transition to digital aerial imagery capture at 50cm Ground Sample Distance (GSD) (from 2008 to 2016) and 25cm GSD (as from 2017 till date). This has resulted to 1370 digital aerial imagery already captured (this number will continue to change as there are jobs that are still being flown which are yet to be recorded). The continuous enhancement of digital camera technology opens for more possibilities of national aerial imagery capture at even greater spatial resolution such as 10cm GSD in the foreseeable future.However, the continuous digital imagery capture has not been without challenges such as the current global Covid-19 pandemic which has resulted in budget reprioritization, the organisation’s technical knowledge transfer from one generation to another together with the determination of the CD: NGI requirement for digital imagery specifications. The organisation values stakeholders’ engagement to ensure relevance, completeness and consistency on the data produced. This is possible through collaboration and partnership between State institutions, the private sector, research, and tertiary institutions through sharing of resources.