[GRASS-user] about resampling DEMs and DEM-derived parameters

[Daniel Lee]

Definitely first resample, then calculate derivatives - otherwise your
results will be totally wrong. Depending on what kind of resampling you do,
you could e.g. take a flat area and see it as slanted in a DEM with reduced
resolution.

--

B.Sc. Daniel Lee
Geschäftsführung für Forschung und Entwicklung
ISIS - International Solar Information Solutions GbR
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2012/6/3 Carlos Grohmann <carlos.grohmann at gmail.com>

>  Hi all.
>
> The other day something popped on my mind, which I think could end in some
> research paper, but
> before I venture into it I decided to ask you guys about it. I did some
> googling and got nothing.
>
> So, considering a large area DEM: if I want its derivatives (slope,
> aspect, etc) in large-scale (larger than
> the original DEM), which one is best, to resample the DEM and then
> calculate the derivatives, or to calculate
> the derivatives and resample them? Much difference expected? The same?
>
> best
>
> Carlos
>
> --
> Prof. Carlos Henrique Grohmann
> Institute of Geosciences - Univ. of São Paulo, Brazil
> - Digital Terrain Analysis | GIS | Remote Sensing -
>
> http://carlosgrohmann.com
> ________________
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