NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum

Are these differences errors or there are formal reason for them? Look at the extract in the permalink:

http://www.openstreetmap.org/?lat=49.0032&lon=-120.498&zoom=12&layers=M

As an experienced mapper, I can understand the sharp cut on the white holes, displaced country border... but I dont understan the color differences for the (obviously) same area object types (light and dark green), the horizontal/vertical tile/grid lines, the very weak contrast between the light-green and light-blue... As I undestand, the SlippyMap is OSM's reference map and should be (among) the best maps created on the most recen/valid OSM source data.

asked 12 May '13, 10:59

sanser's gravatar image

sanser
695383955
accept rate: 5%


The darker green comes from a landuse=forest relation and the lighter green from a natural=wood relation. Additionally there is a boundary=national_park / leisure=nature_reserve combination rendered as an area with many "NR" labels and to the west there is a boundary=national_park without the leisure=nature_reserve tag but with a leisure=park tag resulting in an even lighter green. Somewhat confusing but that's what you get if you want to render many different tags.

permanent link

answered 12 May '13, 12:22

scai's gravatar image

scai ♦
33.3k21309459
accept rate: 23%

edited 12 May '13, 20:13

1

This comes back to the conflicting interpretations of landuse=forest vs natural=wood. In this case they really should be tagged the same on each side of the border, but different mappers follow different conventions.

I keep pushing for the "landuse=forest is for forestry activity" interpretation, but some people use another interpreation, many people dont know/care, and many areas are hard to judge either way. Sigh...

(14 May '13, 10:46) Vincent de P... ♦
2

It's worse than you think: a lot of US forests are just land which is designated National Forest and run by the Forest Service. In many cases there is nary a tree in sight, although this area is mainly forested, but there are gaps http://mc.bbbike.org/mc/?lon=-121.78925&lat=48.93702&zoom=15&num=4&mt0=mapnik-german&mt1=bing-satellite&mt2=hike_bike&mt3=mapquest-satellite. Note the miasalignment of US/Canadian border. North Cascades National Park was also tagged leisure=park (I removed it).

(14 May '13, 11:04) SK53 ♦
Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

By RSS:

Answers

Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text](http://url.com/ "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:

×440
×27
×6

question asked: 12 May '13, 10:59

question was seen: 2,930 times

last updated: 14 May '13, 11:04

NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum