A digital elevation model (DEM) is a typical topographic mapping product and has a wide range of applications in the field of planetary exploration. Chandrayaan-2 Indian mission provides Terrain Mapping Camera (TMC-2) triplet images, namely (Aft(A), Nadir(N), Fore(F)) for lunar DEM and orthoimage generation, similar to Chandrayaan-1 (TMC-1) mission. Triplet image acquisition improves the quality of DEM, and this in turn improves the quality of orthoimages as well. A detailed geometric quality assessment of the data products is desirable for wider applications like lunar morphometric study by planetary geologists. A few datasets are selected on the near and far sides of the moon with different dates of acquisitions and types of terrains to carry out the exercise. This paper describes the generation of DEM with different TMC-2 camera combinations, viz. Nadir-Aft (NA), Nadir-Fore (NF) and Fore-Aft-Nadir (FAN) combinations, orthoimage generation and qualitative and quantitative analysis of both DEM and orthoimage. From the data analysis, it is concluded that amongst NA, NF and FAN combinations of DEM, FAN is better in both qualitative and quantitative aspects and similarly the orthoimage is also better in terms of its geometric accuracy. After evaluation and analysis of multiple TMC-2 FAN DEM and orthoimage w.r.t. external lunar global references like LOLA DEM, SLDEM, WAC DEM and SELENE orthoimage, it is found TMC-2 data products are better in visual quality along with horizontal and vertical accuracies. This paper presents data processing, analysis and data quality evaluation of TMC-2 data products.
展开▼
