It looks like they match well enough, so I'd say the calculations look right (assuming you used the colour scheme I suggested in the other thread). I created a multimap with my summer maps+slope map created with custom DEMs (out of LIDAR data) and compared with my winter maps. I don't see the options for the measure tool, are they already implemented? That said I'm not against the feature, I worked a lot on this kind of maps in the last three years, I'll get back later when I have a little more time. Unfortunately most people is not able to establish if the data they have is good or not, I've seen it in several discussions on dedicated forums. Skitourers use slope maps especially to estimate avalanche risk, so doing slope evaluation on bogus/rough data is not a good idea. Those general purpose DEMs are good for large scale evaluations (flood paths, for example) but not for small scale terrain analysis. You can't see it in a rendering, but data analysis shows the the EUDEM is off by 100 meters about the highest summit in this area. " alt="" class="bbc_img" /> HS_DTM_Piemonte by Maki, su Flickr " alt="" class="bbc_img" /> HS_VFP_DEM1 by Maki, su Flickr " alt="" class="bbc_img" /> HS_EUDEM by Maki, su Flickr Overlap them and see how shape and sometimes position of the reliefs change. I'll try the beta this week and report back but, just to give you a visual clue about how bad DEMs can be here are three screenshots of the same area (Monviso, Piedmont, Italy) rendered with GDALDEM from EUDEM (allegedly an average between ASTER and SRTM), ViewFinderPanorama's DEM1 (nobody really knows the source), and LIDAR scans from the local government (resampled to match the DEM1 resolution and projection). Results can only be as good as the input data.
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