Mapping techniques and Wiki Cleanup Drive: Difference between pages

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This is a page to list things on this wiki to fix. Jot down here anything to fix, and we are setting up a weekend to garden it back to goodness.
==GPS tracklogs==


We are looking for bugs which will take more time to fix than you to tell us about them, which you should please fix yourself. As well as bugs, you may be thinking of larger structural changes to the wiki, things to add and so on.
[[Image:TracklogScreenshot.jpg|thumb|120px|Tracklogs on the GPS screen]]


We want to look at it as if we are total newbies, and help them get started, get involved and get information too.
{{Main|Getting Involved}}


=Planning=
The basic technique for mapping roads, footpaths, ferry crossings, ski routes, etc. is to just turn the GPS on and let it record tracklogs as you move. These can be uploaded directly to OpenStreetmap and displayed on the editing map.


*When: Some weekend day soon TBA
Set the GPS to record points as densely as possible. On the ''Garmin'' systems this is in the ''"Tracks", "Setup", "Resolution: Highest"'' menu.
*Where: We will co-ordinate on IRC during the day in question


=Bugs=
<br clear="both"><!-- Keep the image in its own section -->


Please list your bugs here, big or small
==Points of interest ==


* We're very bad at using MediaWiki's categories -- is that because they're not useful to us? [[User:Jonobennett|Jono]] 08:08, 23 January 2009 (UTC)
[[Image:NotingWaypoints.jpg|frame|right|Geko and Notepad used for [[Points of interest|POI]] logging]]


==JOSM page==
{{Main|Points of interest}}


[[JOSM]]
GPS receivers make it very easy to mark waypoints. On the Geko for example, "Mark", "OK" will insert a numbered waypoint. In the example shown, the cartographer stopped in a pub car park, and marked a waypoint which was stored as number 206.


*Update it to split it out, it's all got FAR to big
Use a notepad, or dictating-machine, to record what that waypoint corresponds to. Although it's usually possible to type this information into the GPS itself, it can be very fiddly.
*link to all the videos on showmedo.com
*split out the installation and running with more memory (-xmx or whatevre it is) with screenshots and really good guides to seperate OS specific pages like [[JOSM/Linux]] and [[JOSM/MacOs]] etc


==front page==
<br clear="both"><!-- Keep the image in its own section -->


*sit down with total newbies and review the front page as an information source, see what they think is wrong. It's beginning to get a little cluttered.
== Digital photography ==


==Beginners Guide==
{{Main|Photo mapping}}
* it's a mostly unhelpful link farm detailing a particular mapping method in infinitely too many pages


=See also=
[[Image:PhotoTimestamp.jpg|frame|left|EXIF data showing creation time]]


* [[WikiProject Cleanup]] - an earlier wiki page listing problems with the Wiki
Digital cameras are useful for recording street names, village names, and other features. Because digtal photographs are timestamped, we can find out where the photographer was at the time (using his GPS log), and mark that as the photograph location.
* [[Machine-readable_Map_Feature_list#Using_Semantic_MediaWiki_in_the_future|Semantic Media Wiki]] - helps to organise all tags inside the wiki ''(see example [http://dev.openstreetmap.org/~edgemaster/semwiki/index.php/Main_Page])''

In the example above, we might put a postbox on the map, wherever the GPS was at 4:48 pm.

Alternatively, you can use specialized software that will correlate your GPS log to your photos. The GPS information will be added to the metainformation inside the images (most commonly, the EXIF metainfo inside JPGs). That way, you can programatically have a list of places where you took a photo. Future releases of OSM software may include support for these "geocoded photographies".

When geocoding photos, be sure that the camera is in sync with the GPS time (test it before trekking!); otherwise the correlation will be displaced.

:''See also: [http://en.wikipedia.org/wiki/Geocoded_photo Wikipedia article on geocoded photos]''

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== City street names ==

[[Image:CityStreets.jpg|frame|right|Sketching the streetnames]]
{{Main|City mapping}}

In dense cities, one-way systems and grids of roads, it can be difficult to record the hundreds of street names encountered.

One method is to sketch how the streets intersect (not to scale), and correlate that later with the pattern of tracklogs generated.

Another technique is the two-pass approach, to record tracklogs, then go back with a printed map of street outlines and fill-in the road names.

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== Satellite/Aerial Imagery ==

Many cities have high resolution georectified aerial photos available for them which can be used to aid mapping. Due to licensing concerns of the derived data, only public domain or CC imagery should be used for this. It's also OK to use [[Yahoo%21_Aerial_Imagery|Yahoo!'s aerial imagery]] as available in the editing applet, and in fact this aids building the map later if you're using the applet.

Before you go mapping, choose the area to map and find it on [http://maps.yahoo.com/ Yahoo! maps]. Make sure you have the satellite tab selected so you're not using the copyrighted map data, and make a printout of the photo (''Don't print out the street map!''). When you go mapping you can take this with you with a pen (gel or ink works best, not ball-point pens unless you take a clipboard, nor pencil because it doesn't show up well) and annotate the photo with which bits are streets/paths, what the names are, and the locations of important places. You may also be able to use the photo to see if there's anything of interest you'd otherwise have missed like a hidden side street or courtyard.

When you get home, open up the editing applet and draw everything as you've noted down. Because you took the satellite photo into the field, you already know where everything is, and don't get confused about whether that green blob next to the black blob is a path or just a copper roof.

== Voice recording ==

{{Main|Audio mapping}}

[[Image:VoiceRecording.png|right]]

I have found voice recording to be the medium of choice mapping by bike. I started using paper as above, but found the continuous stopping and starting was time consuming and a killer on the knees.

[[Image:VoiceRecorder.jpg|right]]

If you display the tracks you collect as connected (e.g. turn on the option in JOSM) you can see the order of your route, so all you need to do is record "left into <street name>" and "dead end", together with "pub The <whatever> at loop" (by which I mean I did a circle on my bike to mark it on the track, much quicker than fiddling with the GPS to mark a waypoint). Perhaps a touch more context, but the briefer the better when playing back.

<br clear="both"><!-- Keep the image in its own section -->

== Video ==

{{Main|Video mapping}}

For those driving alone who can't stop to take notes: mount a video camera (or digital camera in "movie" mode) somewhere that it can see roadsigns, and leave it recording for the duration of your journey.

Afterwards, note the timestamp of anything interesting in the video (e.g. "Shops on the left between 1:32 and 1:37") and correlate that with the GPS tracklog.


==Preprinted forms and outline maps==

[[Image:PreprintedFormExample.png|right|frame|Junction survey form]]

{{Main|Planning and preparation}}

Having a simple outline of an area to fill-in, or a structured method of data-gathering (such as Mapchester's junction-recording form) can make it easier to correlate what is seen on the ground, with the overall area.

==Long Journeys==

{{Main|Long journeys}}

In some cases, you may be away from a computer for an extended period, and the number of trackpoints your GPS holds can become a severely limiting factor. You may need to increase the interval between trackpoints, consider using a different model of GPS, and plan ahead for extra battery capacity.

== See also ==
* [[Tricks and tips]]
* [[GPS reception]]
* [[Using GPS in vehicles]]
* [[Editing]]

[[Category:Mapping techniques]]

Revision as of 09:46, 23 January 2009

This is a page to list things on this wiki to fix. Jot down here anything to fix, and we are setting up a weekend to garden it back to goodness.

We are looking for bugs which will take more time to fix than you to tell us about them, which you should please fix yourself. As well as bugs, you may be thinking of larger structural changes to the wiki, things to add and so on.

We want to look at it as if we are total newbies, and help them get started, get involved and get information too.

Planning

  • When: Some weekend day soon TBA
  • Where: We will co-ordinate on IRC during the day in question

Bugs

Please list your bugs here, big or small

  • We're very bad at using MediaWiki's categories -- is that because they're not useful to us? Jono 08:08, 23 January 2009 (UTC)

JOSM page

JOSM

  • Update it to split it out, it's all got FAR to big
  • link to all the videos on showmedo.com
  • split out the installation and running with more memory (-xmx or whatevre it is) with screenshots and really good guides to seperate OS specific pages like JOSM/Linux and JOSM/MacOs etc

front page

  • sit down with total newbies and review the front page as an information source, see what they think is wrong. It's beginning to get a little cluttered.

Beginners Guide

  • it's a mostly unhelpful link farm detailing a particular mapping method in infinitely too many pages

See also