Re: [Tagging] Topographic Prominence for Peaks

2018-09-28 Thread Joseph Eisenberg
You can’t use those Australian maps for Openstreetmap, unless the government has subsequently released them as public domain. But In the USA and Canada all official topo maps are public domain (I linked the licenses from the proposal page). USGS also has maps of the Arctic and Antarctic. In

Re: [Tagging] Topographic Prominence for Peaks

2018-09-28 Thread Graeme Fitzpatrick
On Fri, 28 Sep 2018 at 15:02, Joseph Eisenberg wrote: > and added a description of how the key saddle of a peak can be found by > looking at a topo map > with contours. > > I also added additional warnings against copying this data from > wikipedia and other sources which are incompatible with

Re: [Tagging] Topographic Prominence for Peaks

2018-09-27 Thread Joseph Eisenberg
Fortunately, when you are finding the prominence of a peak, it matters that the peak and saddle elevations are measured from the same baseline. But thanks for the reminder abou the EGN96 standard. I believe this is also what is used on USGS Topo maps and Opentopomap, which are the sources I

Re: [Tagging] Topographic Prominence for Peaks

2018-09-27 Thread Colin Smale
On 2018-09-27 07:17, Graeme Fitzpatrick wrote: > & when you say survey with GPS, is that accurate enough for an altitude > reading? With my Garmin GPS (which admittedly is 10 - 15 years old, but > _wasn't_ a cheap one!), I can calibrate it in the back yard at 6m ASL, go for > a day trip & when

Re: [Tagging] Topographic Prominence for Peaks

2018-09-27 Thread John Willis
Javbw > On Sep 27, 2018, at 2:17 PM, Graeme Fitzpatrick wrote: > > How do you determine the height of the saddle / peak? There is a lot of GIS data available for named points. Also, there is a lot of topography available as well, so someone manually mapping certian areas could create a

Re: [Tagging] Topographic Prominence for Peaks

2018-09-26 Thread Graeme Fitzpatrick
On Mon, 24 Sep 2018 at 16:06, Joseph Eisenberg wrote: > > That’s why we need to check the height of saddles and peaks “by hand”, or > better yet by survey with GPS. > Joseph, just a technical question, thanks, as I don't understand *any* of the details of what you're wanting to do! :-) How do

Re: [Tagging] Topographic Prominence for Peaks

2018-09-24 Thread Jerry Clough - OSM
On 24/09/2018 07:03, Joseph Eisenberg wrote: Right! Especially on my island, New Guinea.  That’s why we need to check the height of saddles and peaks “by hand”, or better yet by survey with GPS. OSM is the right place for this data, and some map styles and database users will

Re: [Tagging] Topographic Prominence for Peaks

2018-09-24 Thread Dave F
Wouldn't those who need this information be using a contours overlay? Cheers DaveF On 23/09/2018 01:00, Joseph Eisenberg wrote: I've been tagging peaks (natural=peak) with the key prominence= Prominence is a natural feature... ___ Tagging mailing

Re: [Tagging] Topographic Prominence for Peaks

2018-09-24 Thread Joseph Eisenberg
Right! Especially on my island, New Guinea. That’s why we need to check the height of saddles and peaks “by hand”, or better yet by survey with GPS. OSM is the right place for this data, and some map styles and database users will find it useful to analyze data about mountain areas and peaks.

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Yves
I don't see no issue in mapping prominence for those interested in. Just to mention for the sake of the discussion that 'sufficiently accurate DEM' doesn't exists globally. Yves ___ Tagging mailing list Tagging@openstreetmap.org

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Kevin Kenny
On Sun, Sep 23, 2018 at 9:29 PM Bill Ricker wrote: > This all seems like highly specialized, technical data that is not of > general interest, as no one but peak-baggers understand the technical > definition. Many map users seeing this prominence=999m factoid would > jump to the incorrect

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Eugene Alvin Villar
On Mon, Sep 24, 2018, 9:29 AM Bill Ricker, wrote: > Is the OSM primary DB the right repository for this? > Have we accepted being the repository for everything that anyone wants to > map? > (I don't remember hearing a change from "no".) > If people are already mapping whether an amenity=fuel is

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Bill Ricker
This all seems like highly specialized, technical data that is not of general interest, as no one but peak-baggers understand the technical definition. Many map users seeing this prominence=999m factoid would jump to the incorrect conclusion that it was relative to where the (lower of the)

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Kevin Kenny
On Sun, Sep 23, 2018 at 5:40 PM Joseph Eisenberg wrote: > Yes, “prominence” here is a technical term that has only a partially > connection to the subjective “importance” of a peak. > > In general, all peaks with high topographic prominence are considered > important by local people (if anyone

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Joseph Eisenberg
Mf Fly Henry H Rhmmm On Mon, Sep 24, 2018 at 6:38 AM Joseph Eisenberg wrote: > Thanks Kevin > Yes, “prominence” here is a technical term that has only a partially > connection to the subjective “importance” of a peak. > > In general, all peaks with high topographic prominence are considered

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Joseph Eisenberg
Thanks Kevin Yes, “prominence” here is a technical term that has only a partially connection to the subjective “importance” of a peak. In general, all peaks with high topographic prominence are considered important by local people (if anyone lives near them) and mountain climbers, but some peaks

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Kevin Kenny
On Sun, Sep 23, 2018 at 9:34 AM Michael Reichert wrote: > (1) If you assume the earth to be a plane, just order the peaks by their > elevation. It's so simple that I don't give the necessary SQL query > here. If we used a prominence=* key, it would have to be the distance to > the next higher

Re: [Tagging] Topographic Prominence for Peaks

2018-09-23 Thread Michael Reichert
Hi Joseph, Am 23.09.18 um 02:00 schrieb Joseph Eisenberg: > Elevation and prominence can both be calculated from SRTM data, eg by > using Opentopomap tiles and finding the highest contour lines around a > peak, and the lowest near a saddle. > > Prominence and elevation can be calculated by

Re: [Tagging] Topographic Prominence for Peaks

2018-09-22 Thread Warin
I don't think OSM can use wikipedia as a source? Something about incompatible licences. How to calculate prominence will need to documented in OSM rather than refer to wikipoedia. On 23/09/18 11:04, Joseph Eisenberg wrote: For most peaks, it's only necessary to know the elevation of the

Re: [Tagging] Topographic Prominence for Peaks

2018-09-22 Thread Peter Elderson
Edi & change status, I would say. Seems a pretty clear case, just maybe not something many mappers or users are very concerned with. But that's not a problem as long as there is a clear definition, solid data and a steady group of mappers/users. I would say, just do it and document it. Op zo 23

Re: [Tagging] Topographic Prominence for Peaks

2018-09-22 Thread Joseph Eisenberg
For most peaks, it's only necessary to know the elevation of the nearby saddles and peaks to find the prominence. For example, walk to the top of the hill and record the elevation. Look around and find any taller nearby peaks. If there is only 1 taller hill, walk down the ridge line to the lowest

Re: [Tagging] Topographic Prominence for Peaks

2018-09-22 Thread Warin
On 23/09/18 10:00, Joseph Eisenberg wrote: I've been tagging peaks (natural=peak) with the key prominence= Prominence is a natural feature with a use similar to elevation. When I see ele=*, I know how high the top of the peak is, but not how tall the peak is compared to the surrounding land.

[Tagging] Topographic Prominence for Peaks

2018-09-22 Thread Joseph Eisenberg
I've been tagging peaks (natural=peak) with the key prominence= Prominence is a natural feature with a use similar to elevation. When I see ele=*, I know how high the top of the peak is, but not how tall the peak is compared to the surrounding land. For example, a hill in my valley may have