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Hi My name is Petty, I worked as an Intern at Linfiniti after completing my honours degree in GIS last year.

Petronella-Linfiniti member

Petronella Tizora-Linfiniti member

A few months ago l did a project with Linfiniti, so I’ll be sharing on the steps l took and a few cartography hints and tips which might come in handy if you’re interested in making beautiful useful maps. The idea was to create an original, visually attractive and consistent cartographic scheme for representing OSM datasets using QGIS. The first step l took was to build a swatch board.

Swatch Board

The purpose of the swatch board was to help me plan and organize color schemes and feature scales. The advantage of planning your work before you start a project is that you have a basic picture of your output before you start working and you also save time by referring to your initial plan and keeping on track with predefined symbology. My swatch board was a table in Open Office with descriptions of features, colour values and classification fields.

I defined symbology bearing in mind that the map background may be raster (e.g. NASA blue marble or global DEM) or vector (like areas from OSM). I also looked at Google, Bing, OSM and Yahoo maps and websites such as ColourLovers www.colourlovers.com (cool site) to get inspiration on colours to use in my map. All attractive maps seem to have one thing in common….contrasting colours. A normal user should be able to distinguish between freeways and main roads without having a second look at the map. The choices of colors you select for you maps influence the message you send to any viewer. Deciding on which colours to use on a map can be difficult especially if you want to create a unique map. However there are various sites which can help you create themes for your map. Below are some of the sites which l found very useful.

Color Schemer

Color schemer allows you to pick a color or enter its RGB or Hex value and generates matching colors based on your first choice. You can also lighten or darken the scheme. Color Scheme Designer works in an almost similar manner and further allows you to adjust, export and even view colors as a color blind person would see them.

Color Brewer

Color brewer lets you view various color schemes based on the number of classes and scheme you choose for your map. It also provides some advice through “learn more” articles.

ColorLovers

Color lovers is a site where people create and share palettes, patterns and colors. You can also search for palettes and patterns and use them in your own projects.

I generated colors using Color Schemer and used some of them to make a palette in the ColourLovers site. Click on the image to see RGB values for roads in my map.

Roads colour palette generated using coulorlovers

Below is a screen-shot of part of my swatch board

Swatch board

I also created another table which defined scale breaks and line thicknesses for each feature.

Scale breaks and line thicknesses

After all colours, scales and road thicknesses were defined, it was time to get it working on the actual data. Read Part 2 of this document to learn how to download OSM data and load it into Postgres database and apply styles into QGIS .

 

 

 

 

 

 


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