Re: [Tagging] Date of survey

[althio forum]

You could tag date as year and month. Skip the day it is much less relevant.
Which would not help in my case, as I work for several days on the same
survey.

m

On Mon, Dec 22, 2014 at 8:56 PM, Jean-Marc Liotier  wrote:

> On 12/22/2014 08:28 PM, Marc Gemis wrote:
>
>> I always use the tag combination source=survey ;
>> survey:date=year-month-day
>> as described on http://wiki.openstreetmap.org/wiki/Key:survey:date
>>
>
> Whether on the changeset or on the object - whichever is most appropriate,
> automatically adding the current date as survey:date whenever a
> source=survey is entered could be a nice optional editor functionality.
>
>
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Re: [Tagging] Date of survey

[Jean-Marc Liotier]

On 12/23/2014 05:16 AM, Marc Gemis wrote:
On Mon, Dec 22, 2014 at 8:56 PM, Jean-Marc Liotier > wrote:


On 12/22/2014 08:28 PM, Marc Gemis wrote:

I always use the tag combination source=survey ;
survey:date=year-month-day
as described on http://wiki.openstreetmap.org/wiki/Key:survey:date


Whether on the changeset or on the object - whichever is most
appropriate, automatically adding the current date as survey:date
whenever a source=survey is entered could be a nice optional
editor functionality.

Which would not help in my case, as I work for several days on the 
same survey.


Is a precise date necessary ? My use of the survey date could tolerate 
just recording year and month... What moves so fast that the precise day 
is important ? Some things I guess... But then wouldn't the current date 
be a decent default for most cases ?
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Re: [Tagging] Date of survey

[Georg Feddern]

Am 23.12.2014 um 05:16 schrieb Marc Gemis:
Which would not help in my case, as I work for several days on the 
same survey.


as long as changes are not detected for month/years sometimes - some 
days difference between real survey and tagged date would not be any 
problem.
And as long as any change may occure the next day - such tag will be not 
be any "cure-all" - and at least for me no solution at all.


Live with open eyes and change what you recognize - at least as "normal" 
mapper.


If you still want to take it serious:
What purpose does such tag have for anyone?
If there would be a "last_checked tag" - what would you do then?
You can only use it if you want to surveil this object / region regularly.
If so - you have to update _all_ objects of your survey regularly - 
happy history dump!


If you surveil this object / region - do it anyway, even without tag - 
regularly.


Georg

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Re: [Tagging] Date of survey

[Marc Gemis]

I use the exact date to find back my notes, pictures and traces  when
somebody has questions afterwards.
The date is probably useless for anybody else.


regards

m


On Tue, Dec 23, 2014 at 9:18 AM, Georg Feddern 
wrote:

> Am 23.12.2014 um 05:16 schrieb Marc Gemis:
>
>> Which would not help in my case, as I work for several days on the same
>> survey.
>>
>
> as long as changes are not detected for month/years sometimes - some days
> difference between real survey and tagged date would not be any problem.
> And as long as any change may occure the next day - such tag will be not
> be any "cure-all" - and at least for me no solution at all.
>
> Live with open eyes and change what you recognize - at least as "normal"
> mapper.
>
> If you still want to take it serious:
> What purpose does such tag have for anyone?
> If there would be a "last_checked tag" - what would you do then?
> You can only use it if you want to surveil this object / region regularly.
> If so - you have to update _all_ objects of your survey regularly - happy
> history dump!
>
> If you surveil this object / region - do it anyway, even without tag -
> regularly.
>
> Georg
>
>
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Re: [Tagging] Feature Proposal - RFC - (Obligatory vs. optional cycletracks)

[Martin Koppenhoefer]

2014-12-23 8:17 GMT+01:00 Mateusz Konieczny :

> "cycleway=track"
>
> I propose to treat this tag as a special case of fixme - it indicates
> some sort of cycleway parallel to road, without any additional details.
>
> In theory it is possible to add tags that specify surface, side of road,
> width by tags like cycleway:track:left:surface, but it is ridiculous.
>
> Especially specifying geometry (where cycleway is) is
> nearly impossible (and sometimes impossible in any sane way -
> sometimes cycleway is next to road but distance changes).
>
> These things are trivial for tagging as a separate way
> (with highway=cycleway with normal set of tags). Especially
> geometry is defined in a standard way, not by some ridiculous tags.
>


completely agree to everything here. Also adding tags for parallel ways to
the "main highway" would require enormous splitting fragmentation on the
main highway if you start to map the details, leading to a less
maintainable map.

cheers,
Martin
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Re: [Tagging] Tagging Digest, Vol 63, Issue 68

[Ulrich Lamm]

ay, not by some ridiculous tags.
> 
> At least this is my experience from tagging cycleway
> data in Kraków and using this data to render a map of bicycle
> related infrastructure.
> 
> 
> 2014-12-22 23:49 GMT+01:00 fly :
> 
>> As we have tags for different kind of *lane the only problem is
>> cycleway=track.
>> 
>> Now we have two solutions:
>> 
>> 1. deprecate cycleway=track in favour of cycleway=*_track
>> 2. add a new key like bicycle_track=*
>> 
>> My two cents
>> 
>> fly
>> 
>> Am 22.12.2014 um 12:30 schrieb Hubert:
>>> The need to distinguish between obligatory and optional cycle ways
>>> isquite common. Right now it’s done by distinguishing between
>>> bicycle=official/designated and bicycle=yes or bicycle=officialand
>>> bicycle=designated/yes.
>>> 
>>> In a similar way, I think it is better to use something like
>>> bicycle=obligatory instead of cycleway=optionalsince it is more of an
>>> access problem, than a type problem.(I alsodon’tlike
>>> cycleway=opposite)After all the only difference is where one may or must
>>> ride. The cycle way itself does look the same, except for the missing
>> sing.
>>> 
>>> OnMontag, 22. Dezember 2014 02:20Ulrich
>>> Lamm<___ulamm.brem@t-online.de_<mailto:ulamm.b...@t-online.de>> wrote:
>>> 
>>>> Hi all,
>>> 
>>>> 
>>> 
>>>> I've written a proposal for the tags cycleway=obligatory and
>>> 
>>>> cycleway=optional.
>>> 
>>>> 
>>> 
>>>> Now I hope for your comments.
>> 
>> 
>> 
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Re: [Tagging] Tagging Digest, Vol 63, Issue 68

[Martin Koppenhoefer]

Ulrich, please modify the subject line to something that describes the
topic when writing to the list. My suggestion is to remove the
"digest"-option from your personal mailinglist settings (so you'd get the
correct topic for free). Please also remove those quoted parts from your
reply that aren't relevant for the reply (including footers etc.).

thank you,
Martin
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Re: [Tagging] Tagging Digest, Vol 63, Issue 68

[Michael Kugelmann]

Am 23.12.2014 um 11:36 schrieb Martin Koppenhoefer:
Ulrich, please modify the subject line to something that describes the 
topic when writing to the list.
I even would ask NOT AT ALL to comment on digests but on the individual 
posts. Reason: commenting on digests destroys the comment linking => no 
"discussion tree".


BTW: I could point to http://learn.to/quote 
(https://www.netmeister.org/news/learn2quote.html)



Merry Christmas,
Michael.


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Re: [Tagging] Date of survey

[Tod Fitch]

My issue with putting the source=* is that different tags are added at 
different times show it should really be source:item=* (e.g. 
source:max_speed=sign) and then the survey date would also need to be tag 
specific too (e.g. survey:max_speed=*) . That could be a lot of tags which are 
unlikely to be entered by all mappers or properly maintained.

Can't that same information be obtained by looking at the object history? At 
least in JOSM it is pretty easy to pull up the history on any given object and 
see who changed/added/deleted what tags on what date. For me that is enough to 
look back in my notes/gpx traces/etc and get close enough to see what I was 
doing shortly before my commit/upload if there are any questions.


On Dec 23, 2014, at 12:26 AM, Marc Gemis wrote:

> I use the exact date to find back my notes, pictures and traces  when 
> somebody has questions afterwards.
> The date is probably useless for anybody else.
> 
> 
> regards
> 
> m
>  



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Re: [Tagging] Date of survey

[Dave F.]

On 23/12/2014 04:16, Marc Gemis wrote:
Which would not help in my case, as I work for several days on the 
same survey.


+1, although I'm not understanding the point of this tag at all. What 
does it add that isn't already available via the History command (Key: 
H) in Potlatch? Is it not available in other editors?


One advantageous thing would be to click on a GPX trace that's loaded in 
an editor to find out when it was added & by whom.


Dave F.



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Re: [Tagging] Date of survey

[Marc Gemis]

Since I put the date on the changeset, I don't have that issue.
But if the object history works fine for you, please continue so.

regards

m


On Tue, Dec 23, 2014 at 3:33 PM, Tod Fitch  wrote:

> My issue with putting the source=* is that different tags are added at
> different times show it should really be source:item=*
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Re: [Tagging] Date of survey

[Marc Gemis]

The date in the history is the date that the modified object is stored in
osm.
When I did a  number of surveys in the same area a week or a month before,
this modification date is "useless" to find back my notes.
Just having a survey:date on the changeset allows me to pinpoint the date
of the survey exactly.

Take e.g this changeset http://www.openstreetmap.org/changeset/27649274
 The survey was made on Dec 14, but the modification dates will show Dec
23, 2014.
Since I made several walks in that area, it is nice to see the survey date
at once.

There is also no "pollution" of the objects -tags as it is on the changeset.

I'm not forcing anyone to use this method, but it works for me.

BTW, I originally posted about the survey:date tag because the OP asked how
to add a date to a source tag in case of a survey. At least that is how I
interpreted the OP.

regards

m



On Tue, Dec 23, 2014 at 3:48 PM, Dave F.  wrote:

> On 23/12/2014 04:16, Marc Gemis wrote:
>
>> Which would not help in my case, as I work for several days on the same
>> survey.
>>
>
> +1, although I'm not understanding the point of this tag at all. What does
> it add that isn't already available via the History command (Key: H) in
> Potlatch? Is it not available in other editors?
>
> One advantageous thing would be to click on a GPX trace that's loaded in
> an editor to find out when it was added & by whom.
>
> Dave F.
>
>
>
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Re: [Tagging] Date of survey

[SomeoneElse]

On 22/12/2014 19:56, Jean-Marc Liotier wrote:


Whether on the changeset or on the object - whichever is most 
appropriate, automatically adding the current date as survey:date 
whenever a source=survey is entered could be a nice optional editor 
functionality.


In addition to current limited adoption (see 
http://taginfo.openstreetmap.org/keys/date%3Asurvey ) automatically 
adding "date" tags via the editor doesn't tell you anything that you 
can't get from the object history after the fact anyway.  That also 
doesn't do anything for the case where you've checked that e.g. "the 
correct name for a shop is still X".  There used to be something at 
"unexpired.osm24.eu" that could be used to keep track of what you'd 
checked recently, but it doesn't seem to be working at the moment.


There's probably a "good" solution to the problem waiting to be written 
(preferably one that doesn't bloat the OSM database - you don't want to 
create a new version of every item that you check just to add an updated 
date:survey).


Maybe (thinking out loud here) something that could generate a personal 
list of shops in a given area as e.g. garmin waypoints, allowing you to 
change the colour of the waypoint when you've checked a shop in the 
field.  Then back at home a _local_ list is updated with "shop X 
surveyed on Y date", and that shop isn't generated in the list of 
"Garmin shops to check" until some defined time in the future?  If it 
helps anyone, you may be able to borrow from 
https://github.com/SomeoneElseOSM/osmimport_02 which does some of the 
same things, although it's designed for a different job.


Cheers,

Andy




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Re: [Tagging] GPX dates / Date of survey

[Tom Pfeifer]

Dave F. wrote on 2014-12-23 15:48:

On 23/12/2014 04:16, Marc Gemis wrote:

Which would not help in my case, as I work for several days on the same survey.


... History command (Key: H) in Potlatch? Is it not available in other editors?

One advantageous thing would be to click on a GPX trace that's loaded in an editor 
to find out when it was added & by whom.

Dave F.


Don't know about Potlatch, but in JOSM the InfoMode plugin provides you with GPX
information, even on GPS-point level (date, time, speed, trace meta data).

tom

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[Tagging] Accuracy of survey

[Rainer Fügenstein]

while we are at it, imagine the following situation:

mapper A, by means of DGPS, MilStd GPS, crystal ball etc., is able to
achieve an accuracy of, say, a few centimeters and uses it to add new
nodes (POIs) to OSM.

some time later, mapper B with his/her ancestors mechanical GPS device
(*), achieving an accuracy of max., say, 15 meters, surveys the same
area, figures out that (by his/her point of view) POIs added by mapper
A are 15 meters off and corrects their location. 

what is needed here is some tag, saying "don't touch these
coordinates, they've been surveyed with high(est) accuracy".

I heard this argument from an pipeline expert, noting that marker
surveyed with consumer GPS are (for their standards) way off their
real location.

maybe this is a non-issue after all, if consensus is that consumer
GPS accuracy is sufficient enough.

cu

(*) http://www.kenalder.com/measure/excerpts.htm


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Re: [Tagging] Accuracy of survey

[Tom Pfeifer]

I would consider that a non-issue as you said, for those reasons:

- When it comes to GPS traces on objects that don't move (*), the
  beauty of crowdsourcing is on our side. The collection of
  traces over a longer time creates a cloud of traces which
  form a Gaussian bell curve, in density, over the ground truth.

  Thus a junction of two road traced again and again is still
  a good reference point to calibrate aerial imagery.

- We are getting access to increasingly better geo-referenced
  aerial imagery, thus mapping can now use different sources
  and calibrate between them.

The real issue is that in urban areas, lots of object, mostly
houses in absence of GPS traces, have been mapped with offset
imagery and need to be moved a bit.

But this has no implication on tagging.

(*) emphasis on fixed objects, since our friends from OpenSeaMap
have more difficulties creating such repeatable GPS traces since a
ship has no fixed road it would use again and again.

tom

Rainer Fügenstein wrote on 2014-12-23 17:37:


while we are at it, imagine the following situation:

mapper A, by means of DGPS, MilStd GPS, crystal ball etc., is able to
achieve an accuracy of, say, a few centimeters and uses it to add new
nodes (POIs) to OSM.

some time later, mapper B with his/her ancestors mechanical GPS device
(*), achieving an accuracy of max., say, 15 meters, surveys the same
area, figures out that (by his/her point of view) POIs added by mapper
A are 15 meters off and corrects their location.

what is needed here is some tag, saying "don't touch these
coordinates, they've been surveyed with high(est) accuracy".

I heard this argument from an pipeline expert, noting that marker
surveyed with consumer GPS are (for their standards) way off their
real location.

maybe this is a non-issue after all, if consensus is that consumer
GPS accuracy is sufficient enough.

cu

(*) http://www.kenalder.com/measure/excerpts.htm



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Re: [Tagging] Accuracy of survey

[Malcolm Herring]

On 23/12/2014 16:57, Tom Pfeifer wrote:

The collection of
   traces over a longer time creates a cloud of traces which
   form a Gaussian bell curve, in density, over the ground truth.


Except that the position of a node in the DB is the last edited value, 
not the mean position of all historical values.



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Re: [Tagging] Accuracy of survey

[Michael Kugelmann]

Am 23.12.2014 um 17:37 schrieb Rainer Fügenstein:

what is needed here is some tag, saying "don't touch these
coordinates, they've been surveyed with high(est) accuracy".
maybe just add a note to the pipeline (note = "maped mit GPS with 
guaranteed accuracy of ").



Cheers,
Michael.


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Re: [Tagging] Accuracy of survey

[Rainer Fügenstein]

MK> maybe just add a note to the pipeline (note = "maped mit GPS with
MK> guaranteed accuracy of ").

I'm rather thinking of something machine-readable, enabling the editor
to warn the user in case he/she is about to change high precision
data.


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Re: [Tagging] Date of survey

[Friedrich Volkmann]

On 22.12.2014 20:03, jgpacker wrote:
> This suggestion was added to the page having as a goal machine-readability,
> however the suggestion that was there before the page was changed also seems
> to be machine-readable.
[...]
> What do you guys think?

I think that source tags (as well as note tags) should not be
machine-readable, but human-readable.

-- 
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Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Accuracy of survey

[Friedrich Volkmann]

On 23.12.2014 21:39, Rainer Fügenstein wrote:
> I'm rather thinking of something machine-readable, enabling the editor
> to warn the user in case he/she is about to change high precision
> data.

There are quite a couple of editors. Most certainly, some of them will not
implement the feature.

Also, there is no clear line between high and low precision data. Should an
editor warn when the precision is better than 1m, but ignore a precision of
2m? This all depends on the precision of the new data, which the editor does
not know.

-- 
Friedrich K. Volkmann   http://www.volki.at/
Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Accuracy of survey

[Friedrich Volkmann]

On 23.12.2014 17:57, Tom Pfeifer wrote:
> I would consider that a non-issue as you said, for those reasons:
> 
> - When it comes to GPS traces on objects that don't move (*), the
>   beauty of crowdsourcing is on our side. The collection of
>   traces over a longer time creates a cloud of traces which
>   form a Gaussian bell curve, in density, over the ground truth.
> 
>   Thus a junction of two road traced again and again is still
>   a good reference point to calibrate aerial imagery.

There are no GPS traces for pipeline markes. There are traces for roads and
paths only. These traces can bear a systematic error due to reflections
(e.g. under a cliff).

Even if you collect plenty of GPS traces with no systematic error, these
still cannot beat a theodolite triangulation.

> - We are getting access to increasingly better geo-referenced
>   aerial imagery, thus mapping can now use different sources
>   and calibrate between them.

In places where GPS is most inaccurate, e.g. in a gorge covered by woods,
aerial images are inaccurate too, and most of the ground details are not
visible.

-- 
Friedrich K. Volkmann   http://www.volki.at/
Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Accuracy of survey

[Friedrich Volkmann]

On 23.12.2014 17:37, Rainer Fügenstein wrote:
> mapper A, by means of DGPS, MilStd GPS, crystal ball etc., is able to
> achieve an accuracy of, say, a few centimeters and uses it to add new
> nodes (POIs) to OSM.
> 
> some time later, mapper B with his/her ancestors mechanical GPS device
> (*), achieving an accuracy of max., say, 15 meters, surveys the same
> area, figures out that (by his/her point of view) POIs added by mapper
> A are 15 meters off and corrects their location. 
> 
> what is needed here is some tag, saying "don't touch these
> coordinates, they've been surveyed with high(est) accuracy".

I used estimated_accuracy=* or gps_accuracy=* a couple of times, but I doubt
that it prevents other mappers from moving or even deleting them. Some use
editors like Potlatch, so they are not aware of tags. Some do thousands of
edits, all of which are validator based "corrections". They do not ask nor
think nor look at tags, except at those reported by the validator.

-- 
Friedrich K. Volkmann   http://www.volki.at/
Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Feature Proposal - RFC - (Obligatory vs. optional cycletracks)

[Hubert]

Hallo, 

I didn’t want to bring it up on the discussion page yet, but I’m working a way 
to double represent road adjacent cycle ways/ cycle tracks as part of the road 
way and also on the separate  way.

It is far from being ready for representation, but it just fits the discussion 
right now. It has some ideas for distinguishing “near” cycle tracks (separated 
by a curb only) and “far” ones, too. My ideas are being discussed on the German 
mailing list and can be found on this wiki page: 
http://wiki.osm.org/wiki/User:Hubert87/DoubleRepresentation

 

As for having “cycleway=track” on the street-osm-way: There are cases where it 
is better to have it on the road itself. For example when rendering cycle ways 
in lower zoom levels. 

 

Happy Holidays

Hubert

 

From: Martin Koppenhoefer [mailto:dieterdre...@gmail.com] 
Sent: Dienstag, 23. Dezember 2014 09:52
To: Tag discussion, strategy and related tools
Subject: Re: [Tagging] Feature Proposal - RFC - (Obligatory vs. optional 
cycletracks)

 

 

2014-12-23 8:17 GMT+01:00 Mateusz Konieczny :

"cycleway=track"

I propose to treat this tag as a special case of fixme - it indicates 
some sort of cycleway parallel to road, without any additional details.

In theory it is possible to add tags that specify surface, side of road,
width by tags like cycleway:track:left:surface, but it is ridiculous.

Especially specifying geometry (where cycleway is) is
nearly impossible (and sometimes impossible in any sane way -

sometimes cycleway is next to road but distance changes).


These things are trivial for tagging as a separate way 
(with highway=cycleway with normal set of tags). Especially 
geometry is defined in a standard way, not by some ridiculous tags.



completely agree to everything here. Also adding tags for parallel ways to the 
"main highway" would require enormous splitting fragmentation on the main 
highway if you start to map the details, leading to a less maintainable map.

cheers,
Martin

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Re: [Tagging] Accuracy of survey

[Warin]

On 24/12/2014 11:29 AM, tagging-requ...@openstreetmap.org wrote:

Date: Tue, 23 Dec 2014 17:37:34 +0100
From: Rainer Fügenstein 
To: "Tag discussion, strategy and related tools"

Subject: [Tagging] Accuracy of survey
Message-ID: <811143140.20141223173...@oudeis.org>
Content-Type: text/plain; charset=ISO-8859-1


mapper A, by means of DGPS, MilStd GPS, crystal ball etc., is able to
achieve an accuracy of, say, a few centimeters and uses it to add new
nodes (POIs) to OSM.

some time later, mapper B with his/her ancestors mechanical GPS device
(*), achieving an accuracy of max., say, 15 meters, surveys the same
area, figures out that (by his/her point of view) POIs added by mapper
A are 15 meters off and corrects their location.

what is needed here is some tag, saying "don't touch these
coordinates, they've been surveyed with high(est) accuracy".

I heard this argument from an pipeline expert, noting that marker
surveyed with consumer GPS are (for their standards) way off their
real location.

maybe this is a non-issue after all, if consensus is that consumer
GPS accuracy is sufficient enough.

cu

Terms !!

In Metrology (http://en.wikipedia.org/wiki/Metrology) the words 
accuracy, error, etc have specific meaning ..


The common term 'accuracy' or 'error' may mean a normal Gaussian 
distribution taken at 1 sigma or it could mean a rectangular 
distribution taken at 100% coverage ... probably the semi range.


Does it matter?
To the normal user .. no. They too have a consumer grade GPS .. and that 
too will have errors so an offset will be expected.
The professional surveyor may use OSM . But not as a source for 
performing a survey, but as an indication. They should have access to 
professionally defined points and boundaries, past professional surveys.
So I'd say .. No it does not matter. Provided the relationship to the 
adjacent objects is a reasonable representation of what is there so 
recognition and navigation is possible.


Best tag?
I've seen a node with a note  'move to +32.14342 151.345345' (the 
numbers are fictitious). I did as it said and that conformed much better 
to the Bing sat image than before it was moved. So I left it there. 
Troubling no source was stated, that would have been nice. As would have 
been an 'accuracy' statement. If I have seen a statement of 
'uncertainty' with a 'coverage' factor I'd be surprised!


Best survey? Ideally ?
Several GPS traces done on separate days/weeks/months so as different 
satellite constellations are used. Reference could also be made to any 
professional survey marks (usually administered by the government ,these 
will have known locations and 'accuracies'). These can then be applied 
to a satellite image but there are significant shifts depending on 
topography and parallax errors, so caution is required in there 
application over any significant area.


If you don't want something changed .. add a note and say why ... and 
inculcate the source by adding the source tag Things that are very 
well documented tend to be left alone.
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Re: [Tagging] Accuracy of survey

[André Pirard]

  
  
On 2014-12-23 21:39, Rainer wrote :



  MK> maybe just add a note to the pipeline (note = "maped mit GPS with
MK> guaranteed accuracy of ").

I'm rather thinking of something machine-readable, enabling the editor
to warn the user in case he/she is about to change high precision
data.

Notes are just mixed bags.
Doesn't that naturally belong to the realm of source:=*
AFAICS, I see no  for the position, it could be
"position", "location", "coordinates" and possibly contain
accuracy=*, all that up to your imagination, to your expertise and
to a vote.
Using source=* is inappropriate for anything because it covers
everything.
Example: source:position=XYZ pipeline maps 2011; accuracy=2 m

Cheers



  

  André.

  



  


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Re: [Tagging] [Talk-us] Beaver dam? Wrecked bridge? Hallucinatory roads in TIGER?

[johnw]

> 
> 
> It's also time perhaps to talk about a "trailhead" symbol.
> 

+1 being able to tag (then get renderings for) trailheads would be a big plus. 
names should also be rendered in a distinct manner as well. 

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