Talk:Key:source

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Discussions held elsewhere

  • Tagging email list
    • January 2013, "Source tag - deprecated for use on objects?" (This discussion faded out quickly with most replies stating that it was not deprecated, no one could agree if it was worth keeping and the overwhelming majority agreeing that it was certainly premature to deprecate it at that time).

Automatic addition of Source value

Good Idea. Perhabs we schould also have a automaticly filled property, about how mad changes to a object. Like Wikiepdia "Version" tab. Sven Anders 13:43, 28 Jul 2006 (BST)

There is no suggested core value of GPS, is it assumed that if a node is above an uploaded GPX track that that is enough evidence of its source? Dmgroom 00:03, 5 September 2006 (BST)

I think it is assumed, but on the other hand I'd still add the appropriate source tag even in that case when creating the map. After all, some node/segment/way could be above a GPX track just because it's the same road, and yet it could come from a different source... using the appropriate tag in all cases won't hurt. LjL 18:25, 5 September 2006 (BST)

source:name

I actually don't like source:name since it does not comply to the logic used on other tags (e.g. all the lane proposals, the mtb stuff, and so on). I'd love to see a generic foo:bar:source approach, meaning that source:name would be replaced by name:source and the whole concept could be extended to virtually any tag, e.g. opening_hours:source, description:source and so on. I just find source as the last suffix more logical, since the value of the key is actually the source you describe, therefore it is just logic to place the source tag in last place. thoughts? --Marc 18:49, 29 January 2010 (UTC)

source = survey (wiki) vs. GPS (JOSM)

When I create streets etc from a GPS track, I'd like to note that - the wiki suggests using source=survey but JOSM does not offer survey but GPS. As long as JOSM supposes GPS it will be much easier to use it instead of survey. Please clarify and note in wiki (http://wiki.openstreetmap.org/wiki/DE:Map_Features#Erl.C3.A4uterungen and http://wiki.openstreetmap.org/wiki/Key:source) what to do / change JOSM proposals. This comment was not signed, so no easy way of knowing by whom or when this was said!

Personally, after finding these two values exist, I use both but with different meaning. I user source=gps when I actually measured the feature location with my GPS. I use source=survey when I walked within eyesight of the feature and observed its properties and relative location (for instance, I personally saw that the item was there and that it was a bit north of where I was standing, as opposed to being to the south of me, but I had no opportunity to actually walk up and measure its GPS coordinates). Jbohmdk 02:40, 10 June 2013 (UTC)
I have now added this to the page (as a separate edit in case anyone wants to revert this or one of the other edits I just did). Jbohmdk (talk) 23:46, 9 April 2016 (UTC)

Multiple Values

First Entry

(before structure was generated and so probably easy to be overseen after structure had been generated - so added to this chapter retrospectovely)

If I map a road and use many different sources, e.g. Yahoo Image, my own GPS-Trace (which I uploaded after using), GPS traces from other users and also data from http://wiki.openstreetmap.org/wiki/Import/Catalogue/Strassen_NRW . I use different sources in order to map the street most realistic, but with the source tag I can only declare one source. And some people even tag every road with source=survey. Is that good? What can I do / how can I declare more than one source? And if I use Yahoo Image for mapping, do I *need* to declare that I used them?

Thanks in advance. :) ([[[User:Westfa|Westfa]] 13:22, 1. Mai 2009; added retrospectively by --Rennhenn)

official way to assign multiple values for a tag is to separate them with a semicolon, thus you could tag it like source=survey;yahoo or whatnot. i'd say - don't bother too much with it, just set the one that contributed the most. though personally, i only add source when i have used some 3rd party source like landsat etc. --Richlv 19:02, 1 May 2009 (UTC)

Second Entry

If (say) a way has been traced from Yahoo! imagery (hence source=Yahoo), I go there and survey with my bike writing down information like lanes, surface, lit and so on but without a GPS track, should it be source=Yahoo; survey? --Nighto 00:21, 8 May 2010 (UTC)

See above, I asked the same question one year ago :D Seriously, I think that the source key should only be used on an element (a way for example) if the way is very different from what it was before or if you use keys and attributes, that seem "extraordinary". If I map a normal street I don't set the source key on the way, instead I write in the comment of the changeset what I did and where the information come from. And if I used 3rd party sources I add a source key the the changeset. That only works of course if I only use one source. If I said source=Yahoo;survey;landsat;blahblahblah it's not clear for which element I used which source. But if I use different sources for different things I just use different changesets. And of course I add the source key to an element (e.g. node, way...) if another mapper could wonder why I set those values. Under [1] you can find an example how I use the source key on a changeset. [1] On the other hand Openstreetmap is *free*, so *you* can decide how it should be tagged. Other people say the source key on every way makes sense and should be expanded. Just do what you think what makes sense. It's easy to look for the comments and source tags in a changeset with josm, because there is a very nice history function implemented now. :) --westfa 20:31, 17 May 2010 (UTC)
Just put the source=* on the changeset. That way it is easy to see what information came from where. Gnonthgol 22:16, 17 May 2010 (UTC)

Is this tag deprecated?

I've been told on one of the email lists that this key is deprecated and that it should no longer be used on objects but should be used exclusively on changesets. Could someone please confirm that? --Ceyockey 11:57, 2 January 2013 (UTC)

The documentation on the main page has been revised (not by me) to reflect that this tag is to be used on changesets and not objects. --Ceyockey 12:48, 2 January 2013 (UTC)
I made the revert you refer to. I had intended to return a couple of hours later and make some more changes and provide something more neutral, but I see that Frederik Ramm has already made some of the changes I intended. The tagging@openstreetmap.org list currently has discussion going on over this issue, and I assume there will not be agreement. I will state with confidence that adding source tag to the object is not depracted because there is no means of doing this and it appears the majority of people use the source tag on objects. I might be worth giving some though to how your local/regional community uses the source tag. -- Jamicu 15:25, 3 January 2013 (UTC)
Which revert is that? You or someone else seem to have deleted whatever you were responding to, making this part of the discussion impssible to follow. Jbohmdk 03:39, 10 June 2013 (UTC)
I guess this one ;-) --rayquaza (talk) 18:37, 4 July 2013 (UTC)

A source tag on every object in a changeset is very impracticable. Mapper X used Yahoo some years ago, mapper Y refined from Bing 2012 and now we have even better precision from a local geoportal - now beyond moving the nodes, I also need to change the source tag on every object. Thus, having it once in the CS makes it much clearer when which imagery was used.

The exception are objects where other sources have been used compared to the surroundings, such as a new building surveyed by sophisticated GPS techniques. In this case the source tag also works as a warning that it might not yet be visible in the aerial.

Absolute nonsense is the source=HiResAerialImage that I see a lot recently, without saying where from and which year. Now that local councils make their geoportals accessible it is quite important if that was traced from high res Bing 2012, high res local 2011 or high res local 2014. --Polarbear w (talk) 15:58, 17 December 2015 (UTC)

Setting chapters to "historic" - changeset vs. object

There was a recent effort by Jbohmdk to set several chapters on this page to "historic". While I agree that the use of the source tag is moving towards the changeset, it still has its place on individual objects, and in particular giving the source of a particular attribute, such as source:name or source:geometry is absolutely valuable and useful information. So they are not "historical" at all. They are important if the source differs from that of the changeset, or from the surrounding objects. E.g. while all the old buildings can be traced from aerial imagery, a new building could be surveyed by GPS, and it is important to emphasize this. Further some attempts to define values are to narrowing, e.g. there are different forms of survey. --Polarbear w (talk) 08:24, 11 April 2016 (UTC)

Please group the common values for this by scope

Currently, the list of common values is a meaningless mishmash of robotic import source tags (each of which necessarily occurs millions of times) and tags that human mappers may actually want to use. It would be much more useful if the two were separated out from each other in this wiki documentation (but NOT as separate tags). e.g. first a list of common source tag values by human mappers such as survey, gps, local knowledge, bing, etc. Then a list of robotic tag values for bulk imported data.Jbohmdk 03:47, 10 June 2013 (UTC)

I agree. -T99 (talk) 07:36, 21 March 2015 (UTC)
Done (Though I am unsure if a few of the specific source for human mappers are actually robot sources added to the wrong place in the old tables) Jbohmdk (talk) 23:42, 9 April 2016 (UTC)

Survey vs. land survey

A "survey" can mean a lot of things. It can be quite informal ("I drove around the city surveying street name signs to verify TIGER data"), or very professional "land surveying" ("Our licensed engineering team set up our theodolites and laser levels and triangulated the exact position of the node with respect to existing boundary markers with a margin error of less than 0.03 m").

I am not a licensed land surveyor. When I say source=survey, it means that I was there, saw the object and took a note of it. I guess most OSM contributors are not licensed land surveyors. But some undoubtedly are. It would be nice to have a documented way to tag the type and quality of the survey performed. --T99 (talk) 08:18, 15 March 2015 (UTC)

I'd like to add that if you was on site and took a picture, "source=photograph" is really just a means of recording the information that you saw. The same applies to "source=audio" (or was it "source=voice"?) and "source=video" which I think were mentioned earlier but which seem to be forgotten now. On the other hand, if somebody else took the photograph (or video etc.), then "source=photograph" would be better than "source=survey". What if it's an old photograph you took before you started mapping? Or if the photograph reveals details you didn't notice while taking it?

Conversely, if your survey consists of reading signs (e.g. street names), then the survey is just a method of recording the information but the actual source of the information is the signage.

If you want to say "source=survey" accurately, I think you should have made at least some assessment of the object in person and on site, if only just "this way is a residential street in my judgment" or "that building looks like a house".

--T99 (talk) 08:17, 21 March 2015 (UTC)

Bing 2012

This sentence makes little sense to me: "Note that it is still 2012 and not 2013 because of the age of the images." What does it mean? Please elaborate.

It's actually 2015 now and most of the Bing imagery in my region is from fall 2013 ("9/7/2013-10/24/2013") or ca. 2011 ("11/3/2010-4/29/2012").

--T99 (talk) 07:48, 21 March 2015 (UTC)

The year should be the year in which the images where taken. The sentence was added in 2013 and needs to be changed. --rayquaza (talk) 16:44, 19 April 2015 (UTC)
The use of the year that the image was take assumes the user knows that. I would rather see the time/date when the source was added and the user that added it. This could be automated!!!! Or even similar to what is used here to add that information. Would make it easier to immediately see if the data is outdated (for those that know) and contact the author. And it would apply to ALL data sources, not just imagary. Warin61 (talk) 23:48, 5 December 2015 (UTC)
Now that the source tag is only supposed to be on the changeset, not the object, the user and upload time is already there for new uses. Jbohmdk (talk) 22:11, 9 April 2016 (UTC)