cascafico wrote on 20.05.15 12:19:
Carl von Einem wrote
In pre desaster Bing imagery of Nepal I have seen several of those
"shape of roof, but no shadow" but usually interpret them in a different
way: let's assume the house has been built against a hillside, then the
midday sun would be shining at the front of the house and the back of
the house is "leaning" against the hill. No shadow if the roof is rather
flat.
Agree, but if in the close surroundings I see some elements (trees) with
projected shadow, I assume I have a collapsed building. I don't know how
tall trees are, just approximate 5-10meters for a 5-10meters canopy, which
IMO can be compared to 3-5meter height of a rural building.
Anyway I make just assumpions. Of course, if you are exeprienced in
photogrammetry I'll take care of your suggestions.
Please just go on with the way you map, it was just a suggestion that
what you interpret as "flat" in pre disaster imagery might not be.
Anyway all these examples and assumptions are IMHO useless without
screenshots.
Cheers,
Carl
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