Do you need to create a winning map? (And with the Ozri Map Gallery competition coming up at Ozri 2011, the answer should be yes!)
Using ArcGIS to create maps is something that we take for granted now, especially when timelines are involved. Here are some tips to help you create a fantastic map, and also to help you evaluate the maps you currently have.
Hillshades are useful to show terrain that will support analytical surface information like population density, or a thematic overlay like soils. However shading from the hillshade can modify the colours of the main information layer making them artificially dark or washed out. This tends to happen when the hillshade is drawn using the default black to white colours. Instead you can use a warmer grey colour ramp, or make use of the Gamma settings to enhance your hillshade.
Black through white colour ramp
Use different colour ramps so that your Hillshade is supporting other information on your map, not drawing attention away from it. A warm grey colour ramp can work well to maintain critical information.
Adjust the Gamma of your stretched symbology to increase the degree of contrast between the midlevel grey values or a raster.
The online help has a topic called: Improving the display of raster data that fully describes the Gamma setting among others.
There are hundreds of different scale bar and north arrow options that you can use. And while many of them are beautiful and artistic, they are not all going to be appropriate on maps that have a scientific or legal purpose. Choose the map elements that compliment your map’s objective and purpose.
Highlighting shorelines, and other features, to give your maps that extra wow factor is a technique that I get asked about frequently. Normally I tell people to use a vector solution with the Multiple Ring Buffer tool. However there is another way that this effect can be achieved: through rasters and the Euclidean Distance tool.
The first step is to create the raster (you will need the Spatial Analyst extension to run the Euclidean Distance tool). The input to the tool is the polygon that represents your shoreline, or feature. Once you have the raster then work on symbolising the raster with a white to blue colour ramp. You can modify the histogram to specify the amount of white along the shore:
This is the Histogram with no edits made – note the straight line on the histogram.
These are examples of the results after editing the histogram. Note that the closer you move the added vertex to the upper left corner, the less white is shown.
Mapping Centre mappingcenter.esri.com
Remember that one of the best sources of information and ideas is the Esri Mapping Centre. There are blogs, Ask the Cartographer sections, and also downloads or colour ramps, symbols and tools that will help you in creating a successful map.
One of the first steps in creating a map, and the most critical, is knowing what the objective or purpose of the map is. We can extend this further and say that every map tells a good story. Whether it is drawn by hand or computer-generated, if the map tells a good story, then it is a good – successful, map.
Some of the most successful maps use simple mapping methods – shaded area, graduated point, graduated line or choropleth maps. Using techniques like fuzzy lines to symbolise indistinct boundaries, size to symbolise magnitude and hue to symbolise type, result in easily understood, effective, and beautiful maps.
Before you start your next map, think about the map’s story. In a short paragraph, try writing down what it is that you think the map should show. Then think about the easiest way to show it. The objective is to make a map that is striking in its simplicity. You may be surprised at how attractive and compelling it is! And if you stick to the story, your map will be a success!
Think that you have an award-winning map? Show it to the world! Enter it in the Ozri 2011 Map Gallery now (and go in the draw to win an iPad 2)
– Kellie L.