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Digital elevation models are considered the most useful data for dealing with geomorphology. The quality of these models is an\udimportant issue for users. This quality concerns position and shape. Vertical accuracy is the most assessed in many studies and shape\udquality is often neglected. However, both of them have an impact on the quality of the final results for a particular application. For\udinstance, the elevation accuracy is required for orthorectification and the shape quality for geomorphology and hydrology. In this\udstudy, we deal with photogrammetric DEMs and show the importance of the quality assessment of both elevation and shape. For this\udpurpose, we produce several SPOT HRV DEMs with the same dataset but with different template size, that is one of the production\udparameters from optical images. Then, we evaluate both elevation and shape quality. The shape quality is assessed with in situ\udmeasurements and analysis of slopes as an elementary shape and stream networks as a complex shape. We use the fractal dimension\udand sinuosity to evaluate the stream network shape. The results show that the elevation accuracy as well as the slope accuracy are\udaffected by the template size. Indeed, an improvement of 1 m in the elevation accuracy and of 5 degrees in the slope accuracy has\udbeen obtained while changing this parameter. The elevation RMSE ranges from 7.6 to 8.6 m, which is smaller than the pixel size (10\udm). For slope, the RMSE depends on the sampling distance. With a distance of 10 m, the minimum slope RMSE is 11.4 degrees. The\udstream networks extracted from these DEMs present a higher fractal dimension than the reference river. Moreover, the fractal\uddimension of the extracted networks has a negligible change according to the template size. Finally, the sinuosity of the stream\udnetworks is slightly affected by the change of the template size

EVALUATION OF ELEVATION, SLOPE AND STREAM NETWORK QUALITY OF SPOT DEMS