OpenStreetMap
Hello,
there is a problem on the topographic data near Machu pichu (peru) I think there is a lag in the position. we can see the river going up and down the river.
I only contribute via potlatch and can’t do this. Does someone can fix it?
permanent link to the region: osm.org/?lat=-13.1651&lon=-72.5368&zoom=14&layers=C
Hola,
hay una problema en los información topográficos cerca de Machu Pichu (Perú) Creo que hay un retraso en la posición. podemos ver el río subiendo y bajando la montana.
Yo sólo contribuir a través de potlatch y no puede hacer esto. ¿Alguien puede arreglar eso?
enlace permanente a la región: osm.org/?lat=-13.1651&lon=-72.5368&zoom=14&layers=C ———–
Bonjour,
il ya un problème sur les données topographiques à proximité de Machu Pichu (Pérou) Je pense qu’il y a un décalage dans la position. nous pouvons voir la rivière monte et descend la montagne.
J’ai seulement contribuent par l’intermédiaire du potlatch et ne peut pas faire cela. Quelqu’un peut résoudre ce problème?
lien permanent de la région: osm.org/?lat=-13.1651&lon=-72.5368&zoom=14&layers=C
Diskusija
Naudotojo LivingWithDragons komentaras, parašytas 2012 m. gegužės 24 d., 12:13
Hello allophos,
The topographic data is not from the OpenStreetMap data. For the cycle map, I think they use the SRTM topographic data. SRTM is by NASA, using sensors on a satellite. Obviously this allows for the whole planet to have topographic data without very very time consuming (and expensive) ground measurements being taken everywhere. Unfortunately it’s accuracy and precision isn’t as good, and that can be more noticeable in certain areas, such as mountain rivers.
I don’t think anything can be done to fix it. If you have a better source (perhaps for Peru or the region) of height data, then you could generate your own maps using that. Although this will require a lot of technical understanding.
Some information can be found at the following page, and by following links from there. osm.wiki/Relief_maps
Naudotojo Sanderd17 komentaras, parašytas 2012 m. gegužės 24 d., 15:13
If I look at the river, I see it’s aligned with the Bing images. So there’s also the possibility that the Bing images aren’t aligned correctly.
If you live near there, and it’s possible to follow the river while tracing, this would produce a GPX track, so we would know where the exact position is.
With only 2 sources (NASA and Bing), we can’t decide which one is wrong. We need at least a third one (and hopefully, it agrees with one of the two others).
If you aren’t able to do this, I think we should believe Bing.
Naudotojo allophos komentaras, parašytas 2012 m. gegužės 24 d., 16:05
hello,
My understanding is that we can’t modify topographic data! I thought they where imported and so they can be modified.
I live at about 10 000Km of peru, so i can’t tracing with a GPS. I hope someone leaving there can (and will) do it.
Naudotojo Andy Allan komentaras, parašytas 2012 m. gegužės 24 d., 16:52
I have a new source of height data for OpenCycleMap, which I’ll hopefully be adding over the next few months. That should fix places like this, where the SRTM data was missing and the ‘void filling’ gives bad results.
I’d have it live already, but I’ve been delayed by dealing with hardware upgrades, hardware failures and surges in traffic. But I’ll get there!
Naudotojo Sanderd17 komentaras, parašytas 2012 m. gegužės 24 d., 19:57
It’s not that we can’t edit the data. But the data used doesn’t come from OSM but directly from NASA.
We don’t put altitude data in OSM because of certain problems with that.
First of all, it’s difficult to record. Even a good GPS can easily be 10m off in altitude. That is a big number. And you can’t walk everywhere with your GPS. So entire planes would be missing.
Secondly, all those lines would fill the database, and make it a real mess.
And lastly, it’s too easy to shift those lines around and cause inconsistency. Easier than with road data.
So that’s why OSM doesn’t include the altitude data in the main database (except for some important mountains, where we only note the height of the top). And therefore, the makers of those maps that want to use altitude (like Andy) need to get the data elsewhere.
Naudotojo Richard komentaras, parašytas 2012 m. gegužės 24 d., 21:53
Incidentally, there’s no “I only contribute via potlatch and can’t do this” about this. All OSM data can be edited via Potlatch.
Naudotojo Sanderd17 komentaras, parašytas 2012 m. gegužės 26 d., 13:48
Richard, I have to disagree with you. Potlatch is a good beginner’s editor. But sometimes data can’t be edited with Potlatch. I’m thinking of relations of relations, and at some point, someone wanted to delete a huge way (overlapping several countries), and this wasn’t possible (or at least very difficult) via Potlatch too.
Although it has nothing to do with the case above. Some people using Potlatch may need to ask help for achieving difficult goals.
I thank you for providing Potlatch to us (I also used Potlatch at first, and couldn’t handle JOSM) but Potlatch is (as a beginner’s editor) not the solution to all OSM data problems. And it shouldn’t be either.
Naudotojo Richard komentaras, parašytas 2012 m. birželio 22 d., 08:09
@Sanderd17 (sorry, only just spotted this): You can indeed edit relations of relations with Potlatch 2. You might be thinking of Potlatch 1, but that was a long long time ago. :) You can also delete long ways - any failure in doing so will be an API problem, not a P2 problem.