Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-16 Thread Martin Spott
HB-GRAL wrote: > I checked some airports the last days. You can not say that FlightGear > or X-Plane data is accurate and the rest of the mapping world is missing > the "points". Sure, DAFIF (which is the source to most of 'our' runways) is neither error-free nor complete. That's why correctio

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread Curtis Olson
Right -- outside the USA, much of the x-plane airport data is hand entered and submitted by end-users with no quality control other than people are welcome to research and fix problems they find as they find them. I wouldn't be surprised if some of the entries are complete guesses or crazy typos.

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread John Denker
On 09/15/2011 05:15 PM, Martin Fenelon wrote: > I like to think that the positional errors of many (most non US?) > aerodromes are due to mistakes made when changing from one datum to > another. Well, that's not what I think, based on looking at the data. The very first non-US example I look

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread Martin Fenelon
On Thursday 15 September 2011 22:08, HB-GRAL wrote: > No, it looks like the mapping with apt.dat data is inaccurate, at least > outside the United States. > > I checked some airports the last days. You can not say that FlightGear > or X-Plane data is accurate and the rest of the mapping world is >

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread John Denker
On 09/15/2011 03:08 PM, HB-GRAL wrote: > No, it looks like the mapping with apt.dat data is inaccurate, at least > outside the United States. The following repeats an email I sent quite a while ago, which somehow seems to have gotten lost: On 09/10/2011 03:54 PM, HB-GRAL wrote: > I am just cu

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread HB-GRAL
Am 15.09.11 18:12, schrieb Martin Spott: > HB-GRAL wrote: > >> I see now also some differences between OSM and "our" apt.dat [...] > > Note that OSM might be aiming at a different target, they're not > necessarily building a database which meets the specific requirements > in (simulated) aviation.

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-15 Thread Martin Spott
HB-GRAL wrote: > I see now also some differences between OSM and "our" apt.dat [...] Note that OSM might be aiming at a different target, they're not necessarily building a database which meets the specific requirements in (simulated) aviation. Cheers, Martin. -- Unix _IS_ user friendl

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-14 Thread HB-GRAL
Am 12.09.11 09:56, schrieb Alan Teeder: > Google maps are notoriously incorrect on co-ordinates. Even their own road > map overlay does not align perfectly with the scenery. You can check the > accuracy yourself if you have a GPS receiver and visit a set of easily > identifiable points like road ju

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-13 Thread HB-GRAL
Am 12.09.11 00:39, schrieb Martin Spott: > HB-GRAL wrote: > > Exactly, that's a default in Robin's collection. > Hi Martin Yes, sorry, you answered me this one some months before and I just forgot about. It is part of the collection and this probably makes sense. Cheers, Yves -

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-13 Thread HB-GRAL
Am 11.09.11 03:20, schrieb Curtis Olson: > > Asking a cartographer "where is it?" is just about as difficult a question > as asking an astronomer "what time is it?" > > Curt. Hi Curt These are very good questions. I will ask some cartographers and astronomers. Cheers, Yves ---

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-12 Thread Alan Teeder
To: flightgear-devel@lists.sourceforge.net Subject: Re: [Flightgear-devel] Openstreetmap vs. G**gl HB-GRAL wrote: > I am just curious why FlightGear and OSM have the same "accurate" > position, and Google map shows another one. I might not have entirely understood your question (i

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-11 Thread Martin Spott
HB-GRAL wrote: > I am just curious why FlightGear and OSM have the same "accurate" > position, and Google map shows another one. I might not have entirely understood your question (it's late and I'm tired), but one cause to be considered could be that OSM folks might simply have imported from th

Re: [Flightgear-devel] Openstreetmap vs. G**gl

2011-09-10 Thread Curtis Olson
I don't know the specific answer in this case, but it does illustrate one of the surpreme challenges in mixing different gis databases ... you end up with information from different sources, adhering to different standards, appropriate for different scales, using different datums, different surveyi

[Flightgear-devel] Openstreetmap vs. G**gl

2011-09-10 Thread HB-GRAL
Hi all Unfortunately I just run into another problem with my map. This is what I see on my currently generated map using 8.10 taxiway data and 8.50 runway data (this is no reference and a crude mixup of course, I apologize in adnvance): http://maptest.fgx.ch/screens/mapping.png But now, I disc