SK53 has commented on the following diary entries

Post When Comment
Poor man's rendering about 1 year ago

For goodness sake please don't use addr tags to do this: some people use the address data to do things like routing. Using it to store character strings which already looked tacky on maps 30 years ago (tagging for the renderer) just makes everyone's job harder.

Please clean this up! Otherwise you may be forcing EVERY consumer of address data to write special code to remove all your 'poor-man's rendering' tags.

I also think you have guaranteed that any change requests you make regarding rendering will not be treated very seriously. We have hundred's of thousands of contributors and a core team of developers which struggles to reach the hundreds. Ask yourself why these people should prioritise what you want over lots of long-standing requests.

The issue of marking areas of cemeteries happens to be well-known and is discussed and documented on the wiki: I'm sure how well-developed it went from there, but I think we had a reasonable idea of what we wanted to do.

Poor man's rendering about 1 year ago

For shops look at this has many additional shop types rendered.

There is currently work to improve rendering of many items now that the rules have been migrated to CartoCSS rather than the unwieldy raw XML format used previously. However, this needs people to do the work rather than suggest that somehow it's an excuse.

Notwithstanding this, not everything will ever be rendered. It's just not sensible or practicable. Even at the zoom leves now in use things which do have rendering rules are not shown because of clashes between rendering rules. Cartography is as much the art of not showing things as well as showing them.

The Gun, The Blue Posts, and tonight the Monkey Puzzle about 1 year ago

Journalist was Kat Arney free-lancer for BBC, day job at Cancer Research as a Science Communicator. Also a harpist, and according to her twitter bio a keen knitter.

exportation of roads about 1 year ago

You don't say which version of QGis you are using. However, it sounds very much like a known bug with the OSM plugin in versions 1.x.

This living does not handle 64-bit identifiers properly. Current versions of QGis (2.x) use a different method for accessing OSM data. Or you could get a shapefile from Geofabrik or bbbike websites.

For more on the problems with the QGis plying search the OSM help site.

Artwork : only for tourists about 1 year ago

tourism=hotel is the one which bugs me. I spend around 10 years when most weekdays I was living in a hotel, but I sure as hell wasn't a tourist.

Adding in missing roads from South Australian open data about 1 year ago

A fairly naive approach is to buffer existing OSM roads (try 10,20 & 50 metres) and then do a difference operation between the buffered roads & the SA road data. Obviously you'll lose roads within the buffer distance of existing roads but it will probably identify the vast bulk of roads which are missing.

Will probably work best in PostGIS rather than directly in QGIS unless you have loads of memory.

A Social Without Groups about 1 year ago

I liked what I saw of Mikel's SotM-US presentation simply because I felt it would make my life easier in a) organising the Nottingham pub meeting; b) discussing local mapping issues (currently done with a few people through email); and c) sending appropriate welcome / assistance messages to new mappers. (One might characterise these as 'curatorship' roles).

I don't see this as 'social' in the way of Twitter, Facebook, etc: but a pragmatic response to a need to better connect mappers who share an objective, need, or location. Many mappers are not available through any other route than their OSM user name: many, like me, would prefer not to be forced into using 'social' sites just because we contribute to OSM. So, equally, pragmatically the OSM platform is the obvious route.

If someone can come up with a wonderful way to fix the mailing lists (we lost a significant contributor from a local list recently) so that one's mail box isn't deluged by stuff, so that they aren't dominated by the same voices, so that discussion is aimed at moving OSM forward instead of point scoring or deprecation (of people , mapping & tags), then I'd be very happy. However, I don't see it happening, so we have to try something else.

There are two points in Alex's list which I really don't like, they both relate to sending messages to newcomers. I do a bit of this but SomeoneElse has been doing it for over 4 years.

Helping someone finding their way on OSM often is best done privately and we use the OSM message system for this. Forcing stuff out into the open (the wall), or into another channel will just reduce the ability to offer support to new mappers. The wiki discussions I've witnessed over the past 4 years have been in the open, but most have not benefited from this, and most only display (an apparent) consensus because the groups are self-selecting.

One last point, if you look at OSM Stammtischen in Germany the numbers which are meeting regularly and the core number of attendees are both quite small compared with the size of the mapping community. So I'd back Richard's point that the stereotype of extensive local meet-ups is not backed by much.

Mapping of industrial entities over 1 year ago

Whereas I believe OSM should be a good platform for this type of information we have some way to go in developing robust approaches to capturing it. (In fact my recent stuff on shops and other retail outlets is really about looking at the 'value' chain for creating data for a sub-set of commercial entities). I think the same issues are likely to apply for industrial entities.

Broadly speaking I think the problems are:

  • Marking industrial landuse
  • Identifying firms located in these industrial areas
  • Adding some suitable industry sector information by tagging (e.g., ISIC classes)
  • Ensuring comprehensive coverage (initially for selected areas, broadening these out as the basic issues are better understood).

Although there are many directories containing this type of info, many are copyright and most have huge amounts of cruft in them. Even things like company registrations (if available as Open Data) are likely to have poor encoding of industry sector (no one checks, its just for the statisticians, so there are no serious controls).

One starting point is to look at specific industry sectors which tend to have large, obvioius and well-known industrial or manufacturing plants. Off the top of my head: steel works, car factories, shipbuilding, chemical works, petroleum refineries). It's probably easier to get the OSM community to map one or more of these as a challenge.

Fed up with abbreviations in tags over 1 year ago

You can add atm to your list (probably more frequently used than any of the above).

It's fine to peeve, but it works two ways, there are plenty of tags which are completely opaque or confusing to native english speakers too.

IIRC cycleway=asl (advanced stop line) was discussed, but probably on the osm-gb IRC channel and around 67% of current uses are in Great Britain.

Some uses of abbreviations are inevitable, such as ref:INSEE (not obvious if you're not French) or ref:vatin, particularly when these are not supported by editors. Needing to type in cycleway=advanced_stop_line is a good way to discourage their mapping. Your examples happen to all be documented on the wiki, which is a tad surprising. Adding editor support for such keys can hide the naughtiness of illicit use of abbreviations in the value.

Personally I find traffic_sign one of the more opaque keys.

Massachusetts Lake/Pond Cleanup over 1 year ago

It's good to see this cleared up, but it's a shame that the MASSGIS import has been preserved ahead of objects which were mapped by OSM contributors with some degree of local knowledge.

I added Scargo Pond back in 2009 long before any water body data were imported. Back then the Upper Cape looked weird because some landscape features had been imported and others hadn't.

When I look again at this area I am struck that although there is a lot of detail of buildings, conservation areas and so on, there are next to no POIs, or sign of anyone human mapping in the area.

Land Use = Open Space Buffers over 1 year ago

I, and many others use landuse=grass for this purpose. Unfortunately this latter tag is also often (mis-)used for other types of grassland: for instance grass pasturage on farms (clearly landuse=farmland) and grass on sports fields (leisure=recreation_ground). (In many case this has obviously been used becaused it gets rendered : "tagging for the renderer").

The more general term which is widely used is the catch-all "amenity grassland" which covers most types of publically-owned grassland in cities (including sports fields, many public parks as well as the random bits of green space).

In either case tags with dual semantics are a real pain, but I would suggest sticking with landuse=grass, perhaps with some kind of adjectival tag landuse:grass=open_space_buffer, which would allow future disambiguation of the different semantics.

Land Use versus Residential Private Property over 1 year ago

@CloCkWeRX I still don't get exactly why it needs to be in OSM: are you wanting to free cadastral data from commercial constraints,? 'cos it doesn't sound like it when you mention commercial datasets. The type of application you describe sounds mainly of interest to organisations which can afford non-free data.

Most of the applications that use landuse which I am interested in: contesting major planning changes, pollution in watersheds, environmental (habitats/biotopes etc) value of particular areas, and so on - are things which single individuals, small non-commercial groups, and charities are likely to want to do.

@AdamMartin it's nothing to do with database weight (if I understand what you mean by this), although lots of buildings from cadastral data in France are regarded by many mappers as 'bloat' (largely because houses w/o addresses arent very interesting), it's to do with the pain of processing lots of polygons. The nature of OSM is that one does have polygons in polygons.

Land Use versus Residential Private Property over 1 year ago

Broadly speaking don't use landuse for zoning areas.

Use the landuse tags for what is on the ground (which of course ought to correspond with local zoning). Many local administrations will do zoning on a long-term timescale of perhaps several decades. It is no use to anyone to mark areas earmarked for new sections as residential if they are still farmland.

Secondly, dealing with many hundreds of landuse polygons will make landuse data from OSM more or less unusable. Because there is no enforcement that given types of polygons must not overlap, a lot of post-processing is needed on OSM data already. Increasing the number of objects (by perhaps a hundred- to a thousand-fold if you map individual house plots as residential and individual shops as retail. Additionally complex algorithms are then needed to define landuse beyond property boundaries.

I've yet to see a convincing use-case for mapping property boundary details in OSM: enough people have done it to show it's possible, but I'm not aware of anyone with a need to get this data from OSM. Incidentally the vast bulk of use-cases for landuse (including cartographic products) require reasonably generalised polygons.

Think bout boundary of INDIA over 1 year ago

I suspect that you think that the boundary of India should include all of the pre-partition States of Jammu and Kashmir. However it is policy for OpenStreetMap to map what is on the ground. This effectively means that we try and map the Line of Control accurately, rather than areas claimed, but not controlled by India or Pakistan (and indeed China).

The reasons for this are straightforward, OSM is used in countries on both sides of border disputes and therefore it is impossible to adhere to both views of where notional borders might be. Furthermore OSM, unlike, say the maps of the Survey of India, does not serve political purposes. OSM is not a platform for fantasy maps, whether those created by individuals or mandated by legislation by governments.

I realise this may create problems for people in India where it may be an offence to represent the boundaries of India other than according to the states wishes, rather than any accordance with reality. For that purpose I would suggest using an external source for the boundary of India: moving the boundary away from the LoC will be treated as vandalism.

If on the other hand the boundary needs minor tweaks (which I'm sure it does) and you can map them based on personal observation or sources which are open, usable in OSM, and readily available for others to check that such mapping is accurate then do go ahead.

I have also answered this on [OSM Help](

Adding addresses: NG9 over 1 year ago

This is a great piece of work: and an extremely thoughtful insight into the complexities of address mapping.

tagging a green roof? over 1 year ago

Green roofs often have a wide range of different plants depending on a whole host of factors. Relatively few will be seeded with grass.

More often they will have relatively drought tolerant plants, certainly local ones have lots of sedums, and a range of Carophyllaceae (Dianthus, Petrorhagia and others).

For this reason I have used the green_roof=yes tag, see

OSM datasize in PostGIS over 1 year ago

In my experience its often faster to use osmosis to write a pgsql dump & just use copy to do the import (--pgd option in osmosis).

I think you'll find most of the storage overhead is in the geometry columns

Mapping Croydon over 1 year ago

The Food Hygiene ratings have a large number of shops, pubs, schools, hospitals (and a few oddities) with OGL address data including postcodes. Their lists exactly fulfil your idea of hunting down POIs from a list. The data for Croydon LB is here: (warning XML). You can read this with Excel or I could send you a CSV extract with the key info. The lat/lon are actually the postcode centroid.

Addresses from an old survey over 1 year ago

OGL is fine. Even Ordnance Survey OGL is OK, but tedious from an attribution viewpoint. CodePoint Open is not OK, but we can substitute the Office for National Statistics postcode data set which is to all intents and purposes identical.

In addition Food Hygiene, Land Registry and other available data sets (such as Planning Applications) contain a huge amount of useful address information. See my blog Maps Matter for far more about this.

We have huge amounts of OS data under their extended OGL, and as OGL is in effect a more liberal licence there is no problem with OGL.

Would there be any use for a builder=* tag? over 1 year ago

In the UK the phenomenon of a housing estate being known locally after the company which built/developed the land is pretty common. The area of Silverdale in Nottingham was (and may still be) known as the Wimpey Estate (a national firm of house builders); and the Hofton Estate (a local firm of builders) is to the west of Wollaton Road.

The development off Cranbrook Drive in Maidenhead is still called the Sterling Homes estate some 30 years after it was built.

The up-market house developer Berkeley Homes always puts a distinctive marker of properties which it develops including the year of completion.

Recent controversy about 1880s housing in Liverpool (the Welsh Streets) reminds me that there are many examples of 19th century builders leaving their mark in street names, such as these streets which spell out the names of the builders, Owen and Williams.

In other words there is plenty of evidence here that such information tends to stick around in the public memory.

Another reason, particularly for national builders, is that individual building firms often have a particular house-style of building. Wimpey houses of the 1970s are very recognisable, but I'm sure to this is true of other builders. I know architectural historians can often date old buildings with surprising accuracy because certain features reflect specific time-bound trends. I am sure that there are plenty of clues as to the builder in a similar way.