Thursday, 22 December 2011
A snap
Today is the winter solstice here - the north pole was tilted directly away from the sun at 5:30 UTC today. This means the light level is low and the sun's angle is low, so photography has extra challenges. As we drove along a lane near Old Ellerby a sparrow hawk flashed along the hedge and whizzed across the road. I expected it to disappear, but it landed on a fence and stayed long enough to stop and snap a quick photo. The low light didn't help, but it is recognisable.
Saturday, 17 December 2011
'Plane crash
We made a short trip out to eliminate some licence issues. It was a bright, cold winter's day with a lot of traffic on the roads (is there something going on?). We gathered the data to remap an area and headed home by a longer, quieter route that sticks to country roads. The light was still quite good, but in a field Jean saw an aeroplane that looked odd. I stopped the car and saw immediately the reason it looked odd was that it had crashed. It looked like a Piper. I called the police and while I did so another car pulled up. As it happened the driver was a paramedic. He went to the plane and contacted his control centre and was told they knew about it and no-one was hurt.
When I got home the police called to say the plane had crash-landed with engine failure and no one was hurt. Looking at the map the nearest airfield from the crash-site was less than three kilometres away at Mount Airey farm, maybe the pilot was trying to get there and didn't reach it. Having landed a plane there myself I know it is a small, tricky airfield with a sloping runway and a lot of trees around and it's not often manned, so not a great place to land with a problem.
The plane is probably a right-off. The starboard wing and engine look damaged. Looking up the registration it is a Piper PA 23 Apache and at least 35 years old, though planes that old are not uncommon in light aircraft.
Not quite an average mapping session.
When I got home the police called to say the plane had crash-landed with engine failure and no one was hurt. Looking at the map the nearest airfield from the crash-site was less than three kilometres away at Mount Airey farm, maybe the pilot was trying to get there and didn't reach it. Having landed a plane there myself I know it is a small, tricky airfield with a sloping runway and a lot of trees around and it's not often manned, so not a great place to land with a problem.
The plane is probably a right-off. The starboard wing and engine look damaged. Looking up the registration it is a Piper PA 23 Apache and at least 35 years old, though planes that old are not uncommon in light aircraft.
Not quite an average mapping session.
Wednesday, 14 December 2011
Ducking the wrecking ball
The long saga that is the OSM licence change process is picking up pace again. The plan now is to move to the new licence on April 1st next year. That will mean that anything in the database needs to have been added by someone who actively accepted the new licence and contributor terms. So anything else will be archived and removed from the live database.
Declaring the date has been like a light to moths for the few but vociferous deniers. Spreading FUD and generating bonkers conclusions from scraps of truth continues to be their main weapon against the will of the majority. Tricks like calling the change "the deletion" would be worthy of tabloid journalists. One tactic seems to be neither accepting nor declining the new licence to continue to spread uncertainty. I respect people's choices, I deplore the underhand tactics. The LWG continues to hold the high ground of not responding to the provocation.
I have been reviewing the area I'm most interested in, so that by next April there will be no problem areas here. The first weapon is to simply get as many mappers to accept the new licence and CT. So far everyone I have contacted have happily agreed. I have been as neutral as possible in contacting people, not wanting to agree is very much their choice and I respect that. The problem remains that a few people are not responding to messages sent to them. The main reason I suspect is that the email address they registered with is no longer valid. They may have used a work email address and no longer work there for example. I have tried to find people with Google+ accounts, Facebook and Twitter. I've searched for people by name in an area with Google but so far a few stubbornly remain as unresponsive.
There are a few objects created by people who have declined the new licence. These are easy to deal with: simply remap them. I risk losing details added later by acceptors, but having reviewed the bulk of the stuff, the loss is minimal. Indeed, gathering what I normally gather sometimes adds more than is there now, such as speed limits, weight restrictions, bridge heights, lit and so on. I'm leaving some stuff added by people I haven't been able to contact yet, in case they accept. I expect that there will be some places to replace, but I don't mind that. Some of the footpaths will take longer to replace and some will be easier with the better weather in the spring and summer.
I will be remapping stuff created by the FUD mongers too. If they accept at the last minute (which I doubt) there will be nothing of their work left to see, which will be a shame. I was out today gathering some traces and photos (in the gathering gloom) to start that process. I will be happy and a bit smug when I see an email on the lists that is clearly trying to be a wrecking ball and I know that my area is free from such problems.
Declaring the date has been like a light to moths for the few but vociferous deniers. Spreading FUD and generating bonkers conclusions from scraps of truth continues to be their main weapon against the will of the majority. Tricks like calling the change "the deletion" would be worthy of tabloid journalists. One tactic seems to be neither accepting nor declining the new licence to continue to spread uncertainty. I respect people's choices, I deplore the underhand tactics. The LWG continues to hold the high ground of not responding to the provocation.
I have been reviewing the area I'm most interested in, so that by next April there will be no problem areas here. The first weapon is to simply get as many mappers to accept the new licence and CT. So far everyone I have contacted have happily agreed. I have been as neutral as possible in contacting people, not wanting to agree is very much their choice and I respect that. The problem remains that a few people are not responding to messages sent to them. The main reason I suspect is that the email address they registered with is no longer valid. They may have used a work email address and no longer work there for example. I have tried to find people with Google+ accounts, Facebook and Twitter. I've searched for people by name in an area with Google but so far a few stubbornly remain as unresponsive.
There are a few objects created by people who have declined the new licence. These are easy to deal with: simply remap them. I risk losing details added later by acceptors, but having reviewed the bulk of the stuff, the loss is minimal. Indeed, gathering what I normally gather sometimes adds more than is there now, such as speed limits, weight restrictions, bridge heights, lit and so on. I'm leaving some stuff added by people I haven't been able to contact yet, in case they accept. I expect that there will be some places to replace, but I don't mind that. Some of the footpaths will take longer to replace and some will be easier with the better weather in the spring and summer.
I will be remapping stuff created by the FUD mongers too. If they accept at the last minute (which I doubt) there will be nothing of their work left to see, which will be a shame. I was out today gathering some traces and photos (in the gathering gloom) to start that process. I will be happy and a bit smug when I see an email on the lists that is clearly trying to be a wrecking ball and I know that my area is free from such problems.
Monday, 28 November 2011
We paid a quick visit to Woodmansey today to check out a holiday home park that has been in the press recently and some other stuff. Apparently people have been living in the chalets all-year-round when the planning permission doesn't allow this. The place used to be a caravan site but now the caravans have gone to be replaced with smallish chalets on brick foundations. There were still plots for sale and the sales office is still advertising them as retirement homes which is not what the planning permission was for.
The road ways have names and all showed up on the OS Locator anomalies list. We gathered much more information than just the road names: there were more named roads than OS locator indicates, one road name was wrong in OSL, there were a couple of lakes and a public footpath running through the site. It is always worth visiting the scene of these anomalies rather than just use the names, sometimes overwriting the existing surveyed stuff as has happened in the north of the county recently.
A few service roads and buildings on an industrial estate and a couple of extras added, including a newly-built gated community that I sneaked into while the gates were still open for the builders rounded off the visit. On the way home we found a new 40 mph speed limit on a very quiet, narrow and twisty road that is often used by cyclists and horse riders. There was also a bunch of notices up about compulsory purchase of land to the south of Beverley where a much talked-about southern bypass is in the planning stages. It seems a bit bold to compulsorily purchase the land when the planning has not been agreed and there is still, therefore, some debate about the exact route.
The road ways have names and all showed up on the OS Locator anomalies list. We gathered much more information than just the road names: there were more named roads than OS locator indicates, one road name was wrong in OSL, there were a couple of lakes and a public footpath running through the site. It is always worth visiting the scene of these anomalies rather than just use the names, sometimes overwriting the existing surveyed stuff as has happened in the north of the county recently.
A few service roads and buildings on an industrial estate and a couple of extras added, including a newly-built gated community that I sneaked into while the gates were still open for the builders rounded off the visit. On the way home we found a new 40 mph speed limit on a very quiet, narrow and twisty road that is often used by cyclists and horse riders. There was also a bunch of notices up about compulsory purchase of land to the south of Beverley where a much talked-about southern bypass is in the planning stages. It seems a bit bold to compulsorily purchase the land when the planning has not been agreed and there is still, therefore, some debate about the exact route.
Friday, 18 November 2011
Highest and Tallest
We took a ride to the top of Garrowby Hill on the A166. It was a bit wet in the unforecast rain, but it stopped long enough at the top of the hill to not see the view for the murk. This is the highest point in East Yorkshire at about 245m. We did find the trig point hidden away in the grounds of a small water works. I added the runaway lane on Garrowby Hill, but I don't know what others tag these as. I'll probably have to change the tag when I've worked it out.
On the way home we passed Market Weighton and noticed that the bypass has a new name: Giant Bradley Way. William 'Giant' Bradley was the tallest British man ever recorded at 7' 9" (2.108m). Market Weighton, where he was born and lived, is trying to use the Yorkshire Giant to promote itself as a centre for tourism. Which is nice.
On the way home we passed Market Weighton and noticed that the bypass has a new name: Giant Bradley Way. William 'Giant' Bradley was the tallest British man ever recorded at 7' 9" (2.108m). Market Weighton, where he was born and lived, is trying to use the Yorkshire Giant to promote itself as a centre for tourism. Which is nice.
Saturday, 12 November 2011
Why don't Google credit Ordnance Survey?
I've been out checking names of OSM roads. ITO World's OS Locator tiles help to find the places where OS Locator and OSM don't agree. Often on rural roads the names are missing from OSM because there is no name board, but sometimes there are name boards and the difference is because OS Locator does not agree with the name board.
Normally I don't look at Google maps - I'm not interested. Their marking scheme clearly is different from OSM because farm tracks show up as roads for example. When I did look at a Google map page that someone linked to I noticed that an OS Locator name that is wrong on the ground appeared in Google maps. Recently I've checked a few more and whenever OS Locator disagrees with my findings on the ground, so does Google maps. In a couple of occasions OS Locator disagrees with OS StreetView and Google matches OS Locator. I have also used Google's StreetView to look at the name plates where they exist and sure enough the name plate disagrees with the road name on Google's page. Google have the photographs to show the real, on-the-ground names in the StreetView system, but they haven't used them.
Some people might say that the OS names are correct and the name boards might have errors, but I strongly disagree. When the council replaced some damaged name boards locally and one was wrongly spelled, there was a fuss from the people who's road name had apparently changed. They insisted the council put it right, and the council did replace it, though it took nearly three months. My point is that if a name is wrong on the ground people will have it corrected, but if the name is wrong in an OS database no one complains so it doesn't get corrected.
When it comes to Google's naming of roads, the only conclusion I can come to is that somewhere in the supply chain of data that Google uses, OS Locator or some similar OS data is used. Google, or one of their suppliers may have an agreement with Ordnance Survey, but if they are using the open data I wonder why they don't attribute OS?
By the way, why did OS choose "StreetView" as the name of one of their hurriedly-put-together OpenData when Google already used the name for a quite different product?
Normally I don't look at Google maps - I'm not interested. Their marking scheme clearly is different from OSM because farm tracks show up as roads for example. When I did look at a Google map page that someone linked to I noticed that an OS Locator name that is wrong on the ground appeared in Google maps. Recently I've checked a few more and whenever OS Locator disagrees with my findings on the ground, so does Google maps. In a couple of occasions OS Locator disagrees with OS StreetView and Google matches OS Locator. I have also used Google's StreetView to look at the name plates where they exist and sure enough the name plate disagrees with the road name on Google's page. Google have the photographs to show the real, on-the-ground names in the StreetView system, but they haven't used them.
Some people might say that the OS names are correct and the name boards might have errors, but I strongly disagree. When the council replaced some damaged name boards locally and one was wrongly spelled, there was a fuss from the people who's road name had apparently changed. They insisted the council put it right, and the council did replace it, though it took nearly three months. My point is that if a name is wrong on the ground people will have it corrected, but if the name is wrong in an OS database no one complains so it doesn't get corrected.
When it comes to Google's naming of roads, the only conclusion I can come to is that somewhere in the supply chain of data that Google uses, OS Locator or some similar OS data is used. Google, or one of their suppliers may have an agreement with Ordnance Survey, but if they are using the open data I wonder why they don't attribute OS?
By the way, why did OS choose "StreetView" as the name of one of their hurriedly-put-together OpenData when Google already used the name for a quite different product?
Monday, 31 October 2011
Wifi coverage maps
I have been working on a small project for a Community Interest Company who deliver Fi-Wi and who want to display the coverage area of their wifi. They want to show the coverage as bands for their speed of connection: 10Mb, 20Mb, 30Mb etc. They cover a number of areas across the country, especially rural areas. I needed to display a polygon over an OSM map. Their website already has a map on it, using Cloudmade tiles, but with no coverage area on it yet. I took a look at GeoJSON as a way to handle description of polygons and looked at the way OpenLayers handles it. I created a GeoJSON feature collection by hand and tried to display it with OpenLayers. After a frustrating couple of hours I hadn't persuaded it to display my polygons, so I turned to Leaflet. In a few minutes, starting from scratch, I had a map with my polygon on it.
I needed to manage many polygons so I created an AJaX feed to send a GeoJSON feature collection for a bounds box. That way when a map is displayed any of the polygons that should appear on it get sent for that map. The coverage polygons are stored in a database with their maximum extents for north, south, east and west which can them be used to decide which polygons are served for the current bounds box of the displayed map. As usual AJaX is quick and effective. Debugging is fairly easy too since a call to the AJaX server returns a GeoJSON file which is easy to read.
The remaining job was to create a polygon editor so the guys who manage the website can manage the shape of the polygons easily as well as adding new ones as their business expands. This was more intricate, though I'm not sure that I have yet done as much as I would like.
I've enjoyed working with this problem, I hope it helps the company. It has also convinced me that Leaflet is a much more pleasant way to display maps with overlays than wrangling OpenLayers, which may be powerful and very flexible but it always causes me problems.
I needed to manage many polygons so I created an AJaX feed to send a GeoJSON feature collection for a bounds box. That way when a map is displayed any of the polygons that should appear on it get sent for that map. The coverage polygons are stored in a database with their maximum extents for north, south, east and west which can them be used to decide which polygons are served for the current bounds box of the displayed map. As usual AJaX is quick and effective. Debugging is fairly easy too since a call to the AJaX server returns a GeoJSON file which is easy to read.
The remaining job was to create a polygon editor so the guys who manage the website can manage the shape of the polygons easily as well as adding new ones as their business expands. This was more intricate, though I'm not sure that I have yet done as much as I would like.
I've enjoyed working with this problem, I hope it helps the company. It has also convinced me that Leaflet is a much more pleasant way to display maps with overlays than wrangling OpenLayers, which may be powerful and very flexible but it always causes me problems.
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